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Biska je tradicionalna istarska travarica koja se proizvodi postupkom maceracije lišća i grančica imele (Viscum album) u vodeno-etanolnoj bazi, najčešće komovici. Cilj ovog rada je definirati optimalne parametre procesa maceracije imele u vodeno-etanolnoj bazi s obzirom na volumni udio etanola, koncentraciju biljnog materijala i trajanje samog postupka, identificirati i kvantificirati biološki aktivne spojeve u pripremljenim maceratima imele i komercijalnim uzorcima biske, ispitati njihova funkcionalna svojstva (antioksidacijska, antimikrobna i antiproliferacijska), ispitati stabilnost biološki aktivnih spojeva tijekom in vitro gastrointestinalne probave te odrediti fizikalno-kemijske parametre uzoraka (pH vrijednost, sadržaj ukupnih kiselina i ukupnog ekstrakta, kromatske parametre te profil aroma spojeva). Dobiveni rezultati i izvedeni zaključci potvrđuju hipotezu istraživanja da tradicionalna istarska travarica biska sadrži biološki aktivne spojeve imele (fenolne kiseline, flavonoide i kumarine) odgovorne za funkcionalna svojstva biske. Udio fenolnih spojeva u uzorcima ovisi o ispitivanim parametrima maceracije pri čemu statistički značajan utjecaj imaju masena koncentracija biljnog materijala i vrijeme maceracije. Od ispitanih funkcionalnih svojstava, uzorci su pokazali značajnu antioksidacijsku i antiproliferacijsku aktivnost, dok je antimikrobna aktivnost prema odabranim testmikroorganizmima zanemariva. Fizikalno-kemijski parametri uzoraka rezultat su proizvodnog postupka: kvalitete i količine biljnog materijala, kvalitete vodeno-alkoholne baze te procesnih parametara maceracije. Primjenom određenih optimalnih parametara maceracije pri kojima se postiže najveći sadržaj biološki aktivnih spojeva (80 g Lˉ¹ imele, 55 % v/v vodeno-etanolna baza te trajanje maceracije 3 tjedna), moguće je unaprijediti proizvodni postupak u cilju proizvodnje biske boljih funkcionalnih svojstava što će doprinijeti dodatnoj valorizaciji biske kao tradicionalnog, autohtonog proizvoda. Biska is a traditional Istrian herbal spirit produced by maceration of the mistletoe (Viscum album) leaves and twigs in a hydro-ethanolic base, mostly grape marc brandy. The aim of this research is to define optimal maceration parameters of the mistletoe in hydro-ethanolic base with respect to ethanol content, concentration of plant material and duration of the process, to identify and quantify biologically active compounds in prepared mistletoe macerates and biska samples, to examine their functional properties (antioxidant, antimicrobial and antiproliferative), to investigate the stability of biologically active compounds during in vitro gastrointestinal digestion and to determine the physico-chemical parameters of the samples (pH value, content of total acids and total extract, chromatic parameters and aroma compounds profile). The obtained results and derived conclusions confirmed the research hypothesis that the traditional Istrian herbal spirit biska contains biologically active compounds of mistletoe (phenolic acids, flavonoids and coumarins) responsible for the functional properties of biska. The content of phenolic compounds in the samples depends on the tested maceration parameters, where the mass concentration of the plant material and the maceration time have a statistically significant influence. Of the tested functional properties, the samples showed significant antioxidant and antiproliferative activity, while the antimicrobial activity against the selected test microorganisms is negligible. The physicochemical parameters of the samples are the result of the production process: the quality and quantity of the plant material, the quality of the hydro-ethanolic base, and the maceration process parameters. By applying the optimal maceration parameters which resulted in the highest content of biologically active compounds (80 g Lˉ¹ mistletoe, 55 % v/v hydro-ethanolic base and 3 weeks maceration duration), it is possible to improve the production process in order to produce biska with better functional properties. Additionally, that will contribute to the valorization of biska as a traditional, autochthonous product.

Male molekule koje se preferencijalno vežu za hibridne i višelančane strukture DNA i RNA nekovalentnim interakcijama od velikog su znanstvenog interesa, te mogu naći primjenu kao novi i bolji dijagnostički i terapeutski alati. Iako te strukture imaju važnu biološku funkciju unutar stanice mali je broj liganada koji se na njih preferencijalno vežu. Cilj ovog rada je pronaći nove strukturne motive/spojeve koji se preferencijalno vežu na hibridne i višelančane u odnosu na regularne DNA i RNA strukture. Ispitano je nekoliko grupa spojeva: benzotiazolni derivati i cijaninske boje koje su dobivene u suradnji s drugim istraživačkim grupama. Također, istražene su interakcije novosintetiziranih fenantridinskih derivata s DNA. Spojevi s preferencijalnim vezanjem na hibridne i višelančane strukture DNA i RNA odabrani su pomoću brzih metoda probira-kompeticijske dijalize i temperaturnog mekšanja smjesa te RNaza H testa. Daljnjim bioanalitičkim metodama (spektroskopija UV/Vis, fluorescencijska spektroskopija i cirkularni dikroizam) detaljno su okarakterizirane interakcije vezanja malih molekula s odabranim metama. Pokazali smo da se benzotiazolski i cijaninski derivati preferencijalno vežu na hibridne i višelančane strukture DNA i RNA u odnosu na regularne što bi se moglo iskoristiti u antitumorskoj terapiji i za detekciju struktura nukleinskih kiselina. Small molecules able to preferentially bind to specific hybrid and multistranded structures of DNA and RNA by non-covalent interactions are of great scientific interest when it comes to obtaining new and better diagnostic and therapeutic tools. Although these structures have an important biological function inside the cell, there is only a few known ligands which preferentially bind to them. The goal of this thesis is to find new structural motifs/compounds that preferentially bind to hybrid and multistranded structures compared to regular DNA and RNA structures. A small library of several groups of compounds was formed: benzothiazole derivatives and cyanine dyes obtained in collaboration with other research groups. Also, interactions of newly synthesized phenanthridine derivatives with DNA were investigated. Compounds with preferential binding to hybrid and multistranded structures of DNA and RNA were selected using competitive dialysis as a rapid screening method, as well as with melting of mixtures and RNase H assay. Further bioanalytical methods (flourescence and UV/Vis spectroscopy and circular dichroism) were used to characterize their binding interactions with selected targets in detail. The obtained results indicate that certain derivatives from the mentioned classes of compounds preferentially bind to hybrid and multistranded structures of DNA and RNA compared to regular ones, which opens the possibility of their application in antitumor therapy and for the detection of nucleic acid structures.

Polielektrolitni kompleksi i višeslojevi poli(alilamin-hidroklorida) i poli(akrilne kiseline) pripravljeni su u vodenim otopinama NaF, NaCl, NaClO4, LiCl i (CH3)4NCl. Nastanak polielektrolitnih kompleksa po prvi puta istražen je visoko-razlučivom ultrazvučnom spektroskopijom. Ovom metodom ustanovljeno je da interpolielektrolitna neutralizacija rezultira ion-specifičnom agregacijom nabijenih koloidnih kompleksa. Analogan utjecaj iona određen je u slučaju odgovarajućih višeslojeva. Elipsometrom i mikroskopom atomskih sila utvrđeno je da debljina i hrapavost filma raste u nizu F − < Cl− < ClO4 − za anione odnosno (CH3)4N + < Na+ < Li+ za katione. Nadalje, ustanovljeno je da hidrofobnost višesloja također slijedi opisani trend za anione kada je polikation završni sloj filma. Zagrijavanjem polielektrolitnih višesloja tijekom njihove priprave potisnut je specifičan utjecaj iona na površinsku hrapavost i močivost zbog reorijentacije i migracije polimernih lanaca na međupovršini višesloj/zrak. Naposlijetku, provedeno istraživanje ukazuje na značajnu korelaciju između procesa interpolielektrolitne neutralizacije u otopini i na površini. Polyelectrolyte complexes and multilayers of poly(allylamine hydrochloride) and poly(acrylic acid) were prepared in aqueous solutions of NaF, NaCl, NaClO4, LiCl, and (CH3)4NCl. The formation of polyelectrolyte complexes was investigated for the first time by high-resolution ultrasonic spectroscopy. Using this method, it was established that interpolyelectrolyte neutralization results in ion-specific aggregation of charged colloidal complexes. Analogous influence of ions was observed in the case of corresponding multilayers. Using ellipsometer and atomic force microscope, it was determined that the thickness and roughness of the film increases in the sequence F− < Cl− < ClO4 − for anions and (CH3)4N + < Na+ < Li+ for cations. Furthermore, it was found that the hydrophobicity of the multilayer also follows the described trend for anions when a polycation is terminating layer of the film. By heating polyelectrolyte multilayers during their preparation, the specific influence of ions on surface roughness and wettability was suppressed due to the reorientation and migration of polymer chains at the multilayer/air interface. Finally, the conducted research indicates a significant correlation between the process of interpolyelectrolyte neutralization in solution and on the surface.

Primjenom niza modernih računalnih metoda dobiven je detaljan uvid u interakcije koje antagonist istradefilin ostvaruje s adenozinskim A2A receptorom. Temeljem identifikacije strukturnih elemenata koji najviše doprinose vezanju, dizajnirani su derivati većeg afiniteta. Osim konvencionalnog pristupa koji uključuje uvođenje novih funkcionalnih skupina, primijenjena je i modifikacija deuteriranjem čime je postignuto poboljšano vezanje istradefilina u A2A receptor. U ovom radu izotopna supstitucija predstavlja originalan koncept moduliranja farmakodinamičkih svojstava, a dobiveni rezultati ukazuju na veću učinkovitost istradefilina obogaćenog deuterijem što bi se moglo iskoristiti za poboljšanje njegovog farmakoterapijskog profila u liječenju Parkinsonove bolesti. By utilising a series of modern computational methods, a detailed insight into the interactions of the antagonist istradefylline with the adenosine A2A receptor was obtained. Based on the identification of structural elements that contribute the most to binding, higher affinity derivatives were designed. In addition to the conventional approach that includes the introduction of new functional groups, modification by deuteration was also applied, which achieved improved binding of istradefylline to the A2A receptor. In this work, isotopic substitution represents an original concept of modulating pharmacodynamic properties, and the obtained results indicate a greater efficiency of deuterium-enriched istradefylline, which could be used to improve its pharmacotherapeutic profile in the treatment of Parkinson's disease.

U ovom radu opisana je sinteza nekoliko klasa derivata benzimidazola i benzotiazola kojima je ispitana antiproliferativna i antioksidativna aktivnost. U linearnoj višestupanjskoj sintezi novih konjugata benzazola primijenjeni su klasični sintetski pristupi kao i neke suvremene sintetske metode, uključujući sintezu u ekološki prihvatljivim otapalima ili sintezu potpomognutu mikrovalovima. Novi akrilonitrilni derivati N-supstituiranih derivata benzazola 32‒71 i 77‒107 priređeni su aldolnom kondenzacijom odgovarajućih cijanometilbenzazola s benzaldehidima supstituirani promjenjivim brojem metoksi i hidroksi skupina te 4-N,N-dimetilamino i 4-N,N-dietilamino skupinom. Derivati Schiffovih baza supstituirani benzimidazolom 117‒132 priređeni su kondenzacijom N-supstituiranih 2-aminobenzimidazola 108‒115 s odgovarajućim 4-N,N-dimetilamino i 4-N,N-dietilamino supstituiranim benzaldehidima. Derivati iminokumarina i kumarina 134‒149 te amidino-supstituirani derivati kumarina 164‒175 priređeni su ciklokondenzacijom različito supstituiranih 2-hidroksibenzaldehida s odgovarajućim 2-cijanometilbenzimidazolima, te iz kumarinskih aldehida reakcijom kondenzacije s odgovarajućim 4-amidino-supstituiranim 1,2-fenilendiaminima uz korištenje p-benzokinona kao oksidansa. Amidino-supstituirani benzimidazoli 193‒216 priređeni su kondenzacijom 5-supstituiranih salicilaldehida s odgovarajućim 4-amidino-supstituiranim 1,2-fenilendiaminima. Amidino-supstituirani benzotiazoli 179‒181 i 216‒227 priređeni su iz različito supstituiranih 2-hidroksibenzaldehida i odgovarajućih zwitter iona u ledenoj octenoj kiselini. Metoksi-supstituirani karboksamidi 235‒262 priređeni su kondenzacijom benzoilnih klorida s N-supstituiranim derivatima 2-aminobenzimidazola. Hidroksi-supstituirani amidni derivati N-benzimidazola 263‒268 i 280‒286 priređeni su uklanjanjem zaštitnih metoksi skupina, korištenjem BBr3 na niskim temperaturama, te benzilnih zaštitnih skupina katalitičkim hidrogeniranjem uz Pd/C u metanolu. Amidino-supstituirani derivati benzamida 289‒293 priređeni su kiselo-kataliziranom Pinnerovom reakcijom iz odgovarajućih cijano-supstituiranih polaznih spojeva. Strukture novosintetiziranih spojeva potvrđene su 1H i 13C NMR spektroskopijom, a nekim je spojevima struktura dodatno okarakterizirana i masenom spektrometrijom. Svim priređenim spojevima ispitana je antiproliferativna aktivnost in vitro na niz staničnih linija humanih karcinoma i zdravih stanica, dok je ispitivanje antioksidativne aktivnosti in vitro provedeno primjenom spektroskopskih metoda DPPH, FRAP i ABTS. Amidino-supstituiranim derivatima 164‒175 i 179‒181 ispitana je antiviralna aktivnost in vitro na nekoliko sojeva virusa, te su neki od derivata pokazali jako dobru i selektivnu aktivnost prema pojedinim sojevima virusa. Derivatima Schiffovih baza 117‒132 te amidino-supstituiranim benzazolima 193‒216 i 217‒228 ispitana je i antibakterijska aktivnost prema Gram pozitivnim i Gram negativnim bakterijama. Iz dobivenih rezultata ispitivanja biološke aktivnosti i SAR studije, utvrđeno je da na antioksidativnu aktivnost značajno utječe broj metoksi i hidroksi skupina na fenilnom prstenu, te supstituent na dušikovom atomu benzimidazolne jezgre. Najizraženiji utjecaj na povećanje antiproliferativne aktivnosti pokazuje 4-N,N-dietilamino skupina smještena na položaju 7 kumarinskog prstena i fenilnom prstenu akrilonitrilnih derivata, te izobutilni supstituent na N atomu benzimidazolne jezgre. Nekima od najaktivnijih derivata benzazola dodatno su ispitani mehanizmi biološkog djelovanja, te je tako utvrđeno da neki derivati akrilonitrila i iminokumarina djeluju kao inhibitori polimerizacije tubulina, dok je amidnim derivatima ispitana i antioksidativna aktivnost u stanicama. Dokazano je i da najbolju antivirusnu aktivnost ima kumarinski derivat benzimidazola supstituiran nesupstituiranim amidinom koji inhibira ranu fazu replikacijskog ciklusa virusa, odnosno sintezu virusne RNK. This thesis describes the synthesis of several classes of benzimidazoles and benzothiazoles in order to investigate their antiproliferative and antioxidant activity. By using multi-step linear synthesis of new benzazole conjugates, classical synthetic approaches as well as some modern synthetic methods, including synthesis in environmentally friendly solvents or microwave-assisted synthesis, were applied. New acrylonitrile derivatives of N-substituted benzazoles 32‒71 and 77‒107 were prepared by aldol condensation of the corresponding cyanomethylbenzazoles with benzaldehydes with a variable number of methoxy and hydroxy groups and 4-N,N-dimethylamino and 4-N,N-diethylamino groups. Benzimidazole derived Schiff bases 117‒132 were prepared by condensation of N-substituted 2-aminobenzimidazoles 108‒115 with corresponding 4-N,N-dimethylamino and 4-N,N-diethylamino-substituted benzaldehydes. Iminocoumarin and coumarine derivatives 134‒149 and amidino-substituted coumarine derivatives 164‒175 obtained by cyclocondensation of substituted 2-hydroxybenzaldehydes with corresponding 2-cyanomethylbenzimidazoles as well as from coumarine aldehydes with corresponding 4-amidino-substituted 1,2-phenylenediamines using p-benzoquinone as an oxidant. Amidino-substituted benzimidazoles 193‒216 were synthesized within the condensation of 5-substituted salicylaldehydes with corresponding 4-amidino-substituted 1,2-phenylenediamines. Amidino-substituted benzothiazoles 179‒181 i 216‒227 were prepared by condensation of differently substituted 2-hydroxybenzaldehydes and corresponding zwitter ions in glacial acetic acid. Methoxy-substituted carboxamides 235‒262 were prepared by condensation of benzoyl chlorides with N-substituted 2-aminobenzimidazole derivatives. Hydroxy-substituted amide derivatives of N-benzimidazole 263‒268 and 280‒286 obtained by removing protective methoxy groups, using BBr3 at low temperatures, and benzyl protective groups by catalytic hydrogenation with Pd/C in methanol. Amidino-substituted benzamide derivatives 289‒293 were synthesized via acid-catalyzed Pinner reaction from the corresponding cyano-substituted starting precursors. Structures of all newly prepared compounds were confirmed by 1H and 13C NMR spectroscopy while some of them were additionally characterized by mass spectrometry. All prepared compounds were tested for their antiproliferative activity in vitro on a number of human cancer cell lines as well as normal fibroblasts, while antioxidant activity in vitro was performed using spectroscopic DPPH, FRAP and ABTS methods. Amidino-substituted derivatives 164‒175 and 179‒181 were tested for antiviral activity in vitro on several virus strains, and some compounds have shown pronounced and selective activity against some viruses. Schiff base derived benzazoles 117‒132 and amidino-substituted benzazoles 193‒216 and 217‒228 were tested for antibacterial activity against Gram positive and Gram negative bacteria. Results obtained from evaluation of biological activity and SAR studies, revealed that the antioxidant activity is affected by the number of methoxy and hydroxy groups on the phenyl ring as well as the substituent on the nitrogen atom of the benzimidazole nucleus. The strongest impact on the enhancement of antiproliferative activity was observed by 4-N,N-diethylamino group placed at the position 7 on coumarin ring and phenyl ring of acrylonitrile derivatives. The isobutyl substituent on the N atom of the benzimidazole core has the greatest influence on increasing the activity of the synthesized compounds. Some of the most active benzazole derivatives were additionally evaluated to study their mechanisms of biological action and it was confirmed that some of the acrylonitrile and iminocoumarin derivatives have proven to be tubuline polymerization inhibitors, while for amide derivatives the antioxidative activity was tested also in the cells. It has been proven that the most promising antiviral activity has been possessed by coumarine derived benzimidazole substituted with amidine group, being inhibitor of an early step in the replication cycle of virus, respectively the synthesis of viral RNA.

U ovom su radu istražene mogućnosti primjene metode LC-SPE/krio NMR za praćenje kemijskih reakcija i određivanje strukture sporednih produkata i/ili razgradnih produkata on-line koji nastaju u reakciji, s naglaskom na bioaktivne molekule i lijekove. Za razvoj metodologije odabrana su tri modelna sustava. Za svaki modelni sustav istraženi su uvjeti kromatografskog odjeljivanja komponenata reakcijskih smjesâ, zatim parametri za učinkovitu ekstrakciju odabranih analita na SPE-sorbense te utjecaj parametara ekstrakcije na osjetljivost krio-probe NMR. Za identifikaciju i strukturnu karakterizaciju izoliranih spojeva korištene su spektroskopija NMR i tehnika LC-MS. Prvi modelni sustav bili su karbohidrazidi i njihovi derivati koji imaju kelirajuća svojstva te antioksidativno i antiepileptičko djelovanje. Tijekom analize karbohidrazida istražena je osjetljivost sustava LC-SPE/krio NMR. Drugi modelni sustav bio je etodolak koji pripada skupini nesteroidnih protuupalnih lijekova. Analizom 7-etiltriptofola, polazne tvari u sintezi etodolaka, identificirano je i strukturno okarakterizirano 17 onečišćenja. Treći modelni sustav bili su makrozoni, novi amidni konjugati azitromicina i derivata tiosemikarbazida, koji imaju zadovoljavajuće antibakterijsko djelovanje na odabrane susceptibilne i rezistentne bakterijske sojeve. Analizirano je ukupno 6 reakcijskih smjesâ iz triju različitih klasa novosintetiziranih makrozona. Identificirana onečišćenja bila su sporedni produkti i razgradni produkti makrolidne i tiosemikarbazonske strukture, te dijastereomeri makrozona. Konfiguracije dijastereomerâ predložene su na temelju analize spektara NOESY i računskih simulacija molekulske dinamike. Provedeno istraživanje rezultiralo je razvojem pouzdane, brže i učinkovitije metode za analizu složenih smjesa spojeva koristeći pritom znatno manje količine uzorka i organskih otapala u usporedbi s postojećim metodama off-line. Metoda LC-SPE/krio NMR može imati širu primjenu u ekstrakciji, pročišćavanju i karakterizaciji novosintetiziranih spojeva i/ili onečišćenja iz reakcijskih smjesâ. In this doctoral thesis, the possibilities of applying the LC-SPE/cryo NMR method for monitoring chemical reactions and determining the structure of by-products and/or degradation products on-line, with an emphasis on bioactive molecules and drugs, were explored. Three different model systems were explored for methodology development. For each model system, the parameters for chromatographic separation of the reaction mixtures components, as well as parameters for the efficient extraction of the selected analytes on SPE-sorbents, were optimized. Hence, the influence of the SPE-parameters on the NMR cryoprobe sensitivity was also evaluated. NMR spectroscopy and LC-MS were used for identification and structural characterization of the extracted mixture components. The first model system were carbohydrazides and their derivatives, which are known as chelating reagents and also show antioxidative and antiepileptic effects. Sensitivity of LC-SPE/cryo NMR system was determined by analyzing carbohydrazides. Etodolac, a nonsteroidal anti-inflammatory drug, was chosen as the second model system. During the analysis of 7-ethyltryptophol, a starting material in the synthesis of etodolac, 17 impurities were identified and structurally characterized. The third model system were macrozones, new amide conjugates of azitromycin and thiosemicarbazide derivatives which exhibit good antibacterial activity against susceptible and resistant bacterial strains. Six reaction mixtures from three different classes of newly synthesized macrozones were analysed. Identified impurities were classified as macrolide and non-macrolide related by-products and degradation products, as well as macrozone diastereomers. Configurations of diastereomers were proposed on the basis of NOESY NMR spectroscopy data and molecular dynamic simulations. This research resulted in development of a reliable, faster and more efficient methodology for complex mixture analysis using significantly smaller amount of sample and organic solvents in comparison with standard off-line methods. LC-SPE/cryo NMR method can be applied for the extraction, purification and characterization of newly synthesized compounds and/or impurities from reaction mixtures.

U okviru ovog rada pripravljene su i u čvrstom stanju istražene tetraklorokupratne(II), tetrabromokupratne(II) i tetrakloromanganatne(II) soli izvedene iz monoamina, diamina i triamina različitih geometrijskih karakteristika i kemijskih funkcionalnosti. Poseban naglasak pri istraživnju posvećen je strukturnim karakteristikama priređenih spojeva, njihovim termičkim svojstvima, te odabranim magnetskim i električnim svojstvima. Iz difrakcijske strukturne analize priređenih spojeva, te simetrijske i statističke analize literaturno opisanih primjera, postavljena su geometrijska ograničenja i očekivanja za ovaj tip spojeva, koja su omogućila predlaganje smislenih strukturnih modela iz podataka difrakcije na prahu. Predložena je prava simetrija feroelektrične faze etilamonijevog tetraklorokuprata(II) iz podataka neutronske difrakcije, određene su strukture triju aperiodičnih kristala. Izučene su promjene u strukturi metilamonijevih halogenokuprata(II) uslijed supstitucijskog miješanja na položaju halogenidnog iona. Analizirana su magnetska svojstva slojevitih hibrida u ovisnosti o odabranim gradivnim ionima i dimenzionalnosti anorganske okosnice, te su kvantificirane modulacije u magnetskim svojstvima u supstitucijski miješanim kristalima. In this work, tetrachlorocuprate(II), tetrabromocuprate(II) and tetrachloromanganate(II) salts derived from monoamines, diamines and triamines with different geometric characteristics and chemical functionalities were prepared and investigated in the solid state. An emphasis was given to the structural characteristics, thermal properties, and selected magnetic and electrical properties of prepared compounds. Geometric limitations and expectations were derived for this type of materials from the diffraction structural analysis of prepared compounds, and the symmetry and statistical analysis of those described in the literature, which enabled the proposal of meaningful structural models from powder diffraction data. The true symmetry of the ferroelectric phase of ethylammonium tetrachlorocuprate was proposed from neutron diffraction data. Structures of three aperiodic crystals were determined. Changes in the structure of methylammonium tetrahalocuprates(II) due to substitutional mixing of halide ions were quantified. The magnetic properties of the layered hybrids were analyzed in relation to the selection of building ions and the dimensionality of the inorganic framework. Modulations of the magnetic properties in substitutionally mixed crystals were quantified.

ADP-ribozilacija je kovalentna modifikacija koja kontrolira brojne važne stanične procese od bakterija do čovjeka. ADP-ribozilacijski sustav čine ADP-ribozil-transferaze koje prenose ADPribozu na ciljnu (makro)molekulu i ADP-ribozil-hidrolaze koje osiguravaju reverzibilnost procesa. Glavni predstavnici ADP-ribozil-hidrolaza su makrodomenski proteini zastupljeni u sve tri domene života uključujući i viruse. U ovom doktorskom radu istraživana su dva makrodomenska proteina, SCO6735 iz bakterije Streptomyces coelicolor i Mac1 iz virusa SARS-CoV-2. Pokazano je da SCO6735 uklanja ADP-ribozilaciju s jednolančane DNA modificirane na timinu. Na temelju računalnih i eksperimentalnih rezultata predložen je novi katalitički mehanizam hidrolize ADPriboze s DNA karakterističan za skupinu proteina sličnih SCO6735. Makrodomena Mac1 inhibira imunološki odgovor domaćina čime potiče virusnu replikaciju. Stoga ima terapeutski potencijal za liječenje bolesti uzrokovane virusom SARS-CoV-2. U tu svrhu provedena je virtualna pretraga baze malih molekula koja je rezultirala testiranjem 27 spojeva metodom izotermalne titracijske kalorimetrije. Izmjereni afiniteti vezanja potvrdili su dobro vezanje nekoliko spojeva, uključujući FDA-odobrene lijekove Dasatinib i Metotreksat. ADP-ribosylation is a covalent modification that controls essential cellular processes, conserved from bacteria to humans. The ADP-ribosylation system consists of ADP-ribosyl transferases that catalyse the transfer of ADP-ribose to a target (macro)molecule, while ADP-ribosyl hydrolases ensure reversibility. Macrodomain proteins are ADP-ribosyl hydrolases present in all three domains of life and viruses. In this dissertation, two macrodomain proteins were investigated: SCO6735 from Streptomyces coelicolor and Mac1 encoded by the virus SARS-CoV-2. SCO6735 was experimentally shown to act antagonistically to a bacterial toxin known to impair replication by ADP -ribosylation of thymidines in single-stranded DNA. Furthermore, a novel catalytic mechanism of DNA-(ADP-ribose) hydrolysis characteristic of the subgroup of SCO6735-related proteins was proposed. The Mac1 macrodomain is a good therapeutic target, because it inhibits the host immune response, thus allowing virus replication. In search of potential inhibitors, a virtual screening of a compound library was performed. The screening resulted in testing of 27 molecules with the isothermal titration calorimetry. Determined binding affinities suggested good binding of several molecules, including the FDA-approved drugs Dasatinib and Methotrexate.

Na zeolitima strukturnih tipova FAU i MFI (ZSM-5) napravljene su modifikacije tijekom ili nakon sinteze kao bi se poboljšala njihova katalitička aktivnost. Pripremljeni uzorci su modificirani dodatkom mezoporoznog templata N,N,N-trimetilheksadekan-1-amonijeva bromida (CTAB) ili jetkani vodenom otopinom natrijeva hidroksida, kako bi se povećao broj mezopora u kristalima i olakšala difuzija reaktanata do aktivnog mjesta. Jakost aktivnog mjesta ugađana je kationskom zamjenom s ionima Mg2+ , Co2+, Ni2+ i Zn2+ (u vodenoj otopini i mehanokemijski). Utjecaj pojedinog metalnog kationa na broj i jakost Lewisovih i Brønstedovih kiselih mjesta u materijalu praćen je infracrvenom spektroskopijom u vakuumu pomoću adsorpcije probne molekule (deuterirani acetonitril). Broj pojedinih kiselih mjesta dobiven je integriranjem pojedinih krivulja nakon dekonvolucije spektra vezanog D3-acetonitrila, anjihova jakost određena je iz količine nakon zagrijavanja na 150, 200 i 300 °C. Na odabranim uzorcima napravljeni su katalitički testovi konverzije metanola u olefine. Modifications during and after sythesis were made on FAU and MFI (ZSM-5) zeolite type samples in order to enhance their catalytic activity. Prepared samples were modified with mesoporosity template N,N,N-Trimethylhexadecan-1-aminium bromide (CTAB) or etched with water solution of sodium hydroxide to increase the volume of mesopores in crystals and faciliate diffusion of reactnats to the active site. The strength of active sites was modified by cationic exchange with Mg2+ , Co2+ , Ni2+ and Zn2+ ions (in water solution and mechanochemicaly). Effect of metal cation on number and strength of Lewis and Brønsted acid sites was studied by infrared spectroscopy in vacuum with the adsorption of probe molecule (deuterated acetonitrile). The number of various types of acid sites was calculated from the integrated curves after deconvolution of spectra of adsorbed D3-acetonitrile, while their strength is determined after heating at 150, 200 and 300 °C. Catalytic tests of methanol to olefine conversion (MTO) were preformed on selected samples.

Prekomjerna uporaba različitih spojeva te poticanje industrijske i poljoprivredne proizvodnje predstavljaju svakodnevne izazove za znanstvenike i inženjere. Zbog toga je posebna pažnja usmjerena prema obećavajućim naprednim oksidacijskim procesima (NOP), koji se temelje na stvaranju i korištenju reaktivnih kemijskih spojeva za razgradnju (oksidaciju i/ili redukciju) tvari koje se ne mogu ukloniti konvencionalnim oksidansima. Heterogena fotokataliza jedan je od NOP-a gdje radikali nastaju uslijed ekscitacije fotokatalizatora s fotonima s dovoljno energije za stvaranje para elektron-šupljina. Već nekoliko desetljeća titan dioksid (TiO2) je prepoznat kao učinkovit fotokatalizator, međutim njegove modifikacije dobivaju na značaju poradi povećanja fotokatalitičke aktivnosti u području vidljivog spektra. Jedna od takvih modifikacija je dodatak ugljičnih nanocjevčica (eng. carbon nanotubes, CNT). Fotokatalizatori se koriste u suspenziji ili su imobilizirani na inertnom nosaču. Premda su fotokatalizatori u suspenziji reaktivniji od imobiliziranih, uporaba imobiliziranih fotokatalizatora je isplativija. Naime, zbog veličine čestica, izdvajanje fotokatalizatora iz pročišćene vode je složen i ekonomski neisplativ proces, dok se imobilizirani fotokatalizator može upotrijebiti višekratno. Nadalje, uz odgovarajući dizajn reaktora moguće je prevladati ograničenja prijenosa mase i fotona uslijed imobilizacije. Odgovarajući dizajn fotokatalitičkog reaktora važan je poradi iskoristivosti upadnog zračenja i primjenjivosti reaktora. Među nekoliko utvrđenih optimalnih reaktorskih konfiguracija, razmotrene su dvije izvedbe: kaskadni reaktor pločastog tipa (eng. flat plate cascade reactor, FPCR) i reaktor s paraboličnim zrcalima (eng. compound parabolic collector, CPC). FPCR oponaša primjenu u prirodnom okruženju koja se može implementirati uz niske troškove. S druge strane, CPC reaktor je odabran kao „state-of-the-art” u dizajnu zbog najveće učinkovitosti zahvaćanja i usmjeravanja zračenja u sustavu reaktora. Glavni cilj ove disertacije bio je istražiti utjecaj faktora intenzifikacije na učinkovitost i primjenjivost solarne fotokatalize temeljene na razgradnji 1H-benzotriazola (1H-BT). 1H-BT je odabran kao modelno onečišćivalo u istraživanju zbog svoje široke primjene u industriji i svakodnevnom životu, a upravo zbog toga je detektiran u prirodnim vodama u koncentracijama od nano do mikrograma po litri. Dosadašnja istraživanja ukazala su na izravnu fotolizu 1H-BT-a pri UV spektru s najučinkovitijom degradacijom pri UV-C spektru zračenja. Dominantniju ulogu uklanjanja 1H-BT-a u prirodnom okolišu ima neizravna fotoliza ili reakcija s reaktivnim kratkoživućim česticama. 1H-BT je relativno dugo postojan u okolišu budući da se ne razgrađuje u vidljivom spektru zračenja. U površinskim vodama podložan je reakcijama s drugim tvarima pri čemu mogu nastati toksičniji spojevi ukoliko nema mineralizacije. Nedavna istraživanja ukazala su na važnost sudjelovanja radikala u reakcijama razgradnje 1H-BT-a. Ipak, istraživanja su također ukazala na negativan utjecaj klora u NOP-ima zbog nastajanja štetnijih produkata razgradnje po vodeni okoliš. Poradi navedenog, pozornost je usmjerena prema analizi visoke razlučivosti, osjetljivosti i točnosti detektiranja masa koju omogućuje hibridni Q-TOF LC/MS sustav analize (eng. quadrupole time of flight liquid chromatography/ mass spectrometry, kvadrupolno vrijeme leta spregnuto s tekućinskom krmatografijom i masenom spektrometrijom). Stoga, u ovoj doktorskoj disertaciji, cilj je bio istražiti kako faktori intenzifikacije, prvenstveno modifikacija fotokatalizatora, različit dizajn reaktora te upadno zračenje utječu na učinkovitost i primjenjivost solarne fotokatalize. U te svrhe postavljeni su sljedeći ciljevi: (i) razviti matematički model uzimajući u obzir upadno zračenje i brzinu apsorpcije fotona na površini fotokatalizatora (lokalnu ili globalnu) te dinamiku fluida u odabranim reaktorima kako bi se dobila stvarna brzina reakcije; (ii) odrediti mehanizme fotokatalitičke razgradnje 1H-BT-a u korelaciji s različitim pristupima intenzifikacije procesa u uvjetima neutralnog pH te (iii) predložiti optimalne parametre za primjenu fotokatalize u realnim uvjetima na temelju usporedne procjene životnog ciklusa različitih pristupa intenziviranja fotokatalize, te korištenjem sunčevog zračenja. Temeljem zadanih ciljeva, postavljene su četiri hipoteze: (H1) razgradnja 1H-BT-a s fotokatalizatorom TiO2/CNT sa simuliranom sunčevom svjetlošću učinkovitija je u usporedbi s TiO2; (H2) postojeći kinetički modeli s lokalnom volumetrijskom brzinom apsorpcije fotona mogu se modificirati i primijeniti za modeliranje razgradnje 1H-BT-a u FPCR i CPC reaktorima; (H3) fotokatalitički produkti razgradnje 1H-BT-a značajno su manje prisutni u odnosu na rezultate fotolize 1H-BT-a; i (H4) fotokataliza pri sunčevom zračenju s fotokatalizatorom aktivnim i u vidljivom dijelu spektra optimalna je za uvećanje procesa i primjenu u realnim uvjetima na temelju usporedne procjene životnog ciklusa procesa (eng. life cycle assessment, LCA). Dakle, što se tiče prve hipoteze, temeljem dobivenih eksperimentalnih podataka i smanjenja koncentracije 1H-BT-a može se zaključiti kako fotokataliza s TiO2/CNT nije učinkovitija od fotokatalize s TiO2 u oba slučaja primjene FPCR i CPC reaktora. Međutim, daljnja analiza najnovijom metodom visoke rezolucije, hibridnim Q-TOF LC/MS, omogućila je identifikaciju produkata razgradnje nastalih tijekom fotokatalize. S novim uvidom bilo je moguće primijetiti kako je modifikacija TiO2 s CNT-om pokrenula drugačiji reakcijski mehanizam u CPC reaktoru. Primjerice, uslijed raspada triazolnog prstena 1H-BT-a u sustavu se može pojaviti produkt razgradnje s istim fragmentacijskim uzorkom raspada kao 1H-BT. S druge strane, reakcijski put razgradnje 1H-BT-a u FPCR-u bio je vođen hidroksilacijom i raspadom benzenskog prstena. Veća površina imobiliziranog fotokatalizatora u FPCR-u (15,6x) u usporedbi s CPC reaktorom pokazala je da je fotokataliza površinski fenomen te je dodavanje CNT-a doprinijelo adsorpciji. S aspekta toksičnosti produkta razgradnje, adsorpcija pozitivno doprinosi budući da hidroksilirane tvari imaju nešto veći negativan utjecaj na okoliš. Stoga se može reći kako razgradnja 1H-BT-a nije nužno učinkovitija s TiO2/CNT u usporedbi s TiO2 pod simuliranim sunčevim svjetlom. Međutim, s aspekta reakcijskih mehanizama TiO2/CNT doprinosi poboljšanju fotokatalize i ekološki prihvatljivijoj fotokatalizi. Što se tiče druge hipoteze, razvijen je kinetički model s masenom bilancom te je uspješno primijenjen za razgradnju 1H-BT-a neovisno o postavkama reaktora i različitoj formulaciji fotokatalizatora. Uvođenje intrinzičkih parametara omogućilo je određivanje stvarne konstante brzine reakcije za BT (ki=3.54×10−10 s−1W−0.5m1.5) primjenjive u svim postavkama, dok je doprinos formulacije fotokatalizatora i postavki reaktora opisan odgovarajućim indeksima, Ycat=0.769 and YRD=25. Kao što je navedeno u disertaciji, 1H-BT je podložan fotolizi pod UV zračenjem, odnosno UV-C zračenju, dok to nije slučaj s UV-A i UV-B zračenjem. Međutim, pomoću fotokatalizatora i UV/vis zračenja moguće je razgraditi 1H-BT na manje štetne produkte razgradnje. Naposljetku, korištenje prirodnog zračenja poželjno je za proces razgradnje, zbog manje potrošnje energije kao i zbog većeg udjela zračenja. Stoga je određena prethodno spomenuta stvarna konstanta brzine reakcije za 1H-BT, čime je postignut prvi cilj ovog rada. Štoviše, predloženi su mehanizmi razgradnje u korelaciji s različitim procesima intenzifikacije. Naime, dok je u FPCR-u hidroksilacija dominantan reakcijski put cijepanja benzena s naglašenom adsorpcijom kada je korišten TiO2/CNT, u CPC reaktoru put razgradnje ide prema reakciji nukleofilne adicije i cijepanju triazolskog prstena. Time je postignut drugi cilj ovog rada. U konačnici, temeljem komparativne LCA, predložena je fotokataliza pod prirodnim sunčevim zračenjem kao optimalno rješenje za buduće skaliranje. Ovim radom utvrdio se utjecaj različitih intenzifikacijskih faktora na učinkovitost solarne fotokatalize. Određivanje stvarne konstante brzine reakcije omogućit će daljnja proučavanja novih fotokatalitičkih materijala i njihovu bržu implementaciju u pilot i realnim sustavima obrade otpadnih voda. Predloženi mehanizmi razgradnje 1H-BT-a omogućili su utvrđivanje toksičnog utjecaja i razmatranje uklanjanja kako 1H-BT-a tako i drugih onečišćivala i u vodenim sustavima poput podzemnih voda gdje je utvrđena pojava istih. LCA metodologija primijenjena je za proučavanje različitih fotokatalitičkih intenzifikacijskih pristupa te korištenje sunčevog zračenja u odnosu na umjetne izvore zračenja radi utvrđivanja najprihvatljivijeg s aspekta utjecaja na okoliš, što čini predloženi rad pionirskim u užem području inženjerstva okoliša. The intensive use of various compounds and the promotion of industrial and agriculture production are daily challenges for scientists and engineers. Consequently, removing micropollutants from waters has become one of humankind's priorities. Accordingly, the efforts have been directed towards promising advanced oxidation processes (AOPs) based on the generation and use of radicals, powerful chemical species for the removal (oxidation/reduction) of substances that conventional oxidants cannot remove. One of the AOPs is heterogeneous photocatalysis. Radicals are formed after photocatalyst's excitations by photons with sufficient energy for electron/hole pair generation. For several decades, titanium dioxide (TiO2) has been recognized as an efficient photocatalyst. However, modifications of TiO2 are gaining importance due to the photocatalytic intensification in the visible spectra range. One such improvement is the one with carbon nanotubes (CNT). Photocatalysts are either used in suspensions or immobilised on an inert support. Suspended photocatalysts tend to be more reactive. However, the use of an immobilised photocatalyst is more cost-effective and versatile due to the reusability issues. Namely, separating the photocatalyst from purified water is a complex and economically unprofitable process. Moreover, it is possible to overcome mass and photon transfer limitations due to immobilisation with an appropriate reactor design. Furthermore, appropriate reactor design is essential due to the usability of incident irradiation and reactor applicability. Among the few reported optimal reactor designs, two different setups were considered hereby, a flat-plate cascade reactor (FPCR) and a compound parabolic collector (CPC) reactor. The FPCR was chosen since it mimics an outdoor system application which can be implemented at a low cost. Meanwhile, the CPC reactor was selected as the state-of-the-art in design regarding its favourable properties such as the highest effectiveness of irradiation capture in the reactor system. Therefore, the main goal of this dissertation was to study the impact of the intensification factors on the efficiency and applicability of solar photocatalysis based on 1H-benzotriazole (1H-BT) degradation. The photocatalyst modification and reactor setup were selected as intensification factors. Modelled pollutant 1H-BT was chosen due to its wide application in industrial and everyday life, for which it has been detected in natural waters from nano to microgram per litre concentrations. Previous studies have proved direct photolysis of 1H-BT under UV light with the most efficient degradation in UV-C spectra. A more dominant role of 1H-BT removal in the natural environment is indirect photolysis or reaction with reactive transient species. Nevertheless, due to the insensitivity to visible light, 1H-BT is relatively long persistent in the environment. In surface waters, it is subjected to reactions with other species where more toxic compounds can be formed if there is no mineralization. Recent studies have demonstrated the importance of radicals in 1H-BT removal reactions. Yet, a negative impact was reported when chlorine was used in the AOPs due to the generation of more harmful degradation products for the aquatic environment. To avoid such a scenario, an analysis with a high mass resolution, full-scan sensitivity, and mass accuracy provided by a hybrid Q-TOF LC/MS (quadrupole time of flight, liquid chromatography coupled with mass spectrometry) system is gaining attention in the detection of degradation products. Accordingly, the following objectives were established: (i) a development of a mathematical model including irradiation terms and a rate of photon absorption over photocatalyst surface (local or global) and fluid dynamics in chosen reactors to obtain intrinsic reaction rate; (ii) determination of 1H-BT photocatalytic degradation pathways in correlation with different intensification approaches under neutral pH conditions and (iii) proposition of optimal parameters for accurate scale photocatalytic process based on comparative life cycle assessment (LCA) of various photocatalysis intensification approaches and the use of natural sunlight. Based on the dissertation objectives, four hypotheses were formulated. The first hypothesis (H1) states that 1H-BT degradation is more effective with TiO2/CNT photocatalyst under simulated solar light than TiO2. The second hypothesis (H2) states that existing kinetic models with the local volumetric rate of photon absorption can be modified for 1H-BT degradation in FPCR and CPC reactors. The third hypothesis (H3) states that photocatalytic degradation products of 1H-BT degradation are negligible compared to ones obtained by photolysis alone. And the fourth hypothesis (H4) states that photocatalysis under natural irradiation with UV/vis intensified photocatalyst is optimal for scale-up and real-scale application based on the comparative LCA. Therefore, regarding the first hypothesis and observed experimental data of 1H-BT concentration decreasing, it could be concluded that photocatalysis with TiO2/CNT is not more efficient than photocatalysis with TiO2 in both cases when FPCR and CPC reactors were applied. However, further analysis by the newest high-resolution techniques, a hybrid Q-TOF LC/MS, enabled the identification of degradation products formed during photocatalysis. With unique insight, it was possible to identify that modification of TiO2 with CNT had triggered different 1H-BT degradation mechanisms in the CPC reactor. Also, the degradation product with the same fragmentation pattern as the 1H-BT can occur in the system due to triazole ring breakage. On the other hand, the reaction pathway of 1H-BT degradation in FPCR was governed by hydroxylation and benzene ring breakage. Furthermore, the larger surface of the immobilised photocatalyst in the FPCR (15.6x) compared to the CPC reactor demonstrated that photocatalysis is a surface phenomenon. Therefore, the addition of CNT increased adsorption. Regarding the toxicity of degradation by-products, the adsorption was favourable in the FPCR since hydroxylated species pose a slightly greater negative impact on the environment. Therefore, it can be said that 1H-BT degradation is not necessarily more effective with TiO2/CNT compared to TiO2 under simulated solar light. However, from the aspects of reaction mechanisms, TiO2/CNT contributes to photocatalysis enhancement and environmentally friendlier photocatalysis. Regarding the second hypothesis, a kinetic model with mass balance was developed and successfully applied for 1H-BT degradation independently on reactor setup and different photocatalysts formulation. The introduction of intrinsic parameters enabled the determination of the intrinsic reaction rate constant for 1H-BT (ki=3.54×10−10 s−1W−0.5m1.5) applicable in all setups, while the contribution of a photocatalyst formulation and reactor setups was described with appropriate indexes, Ycat=0.769 and YRD=25, respectively. As was discussed in the dissertation, 1H-BT is subjected to photolysis under UV, namely UV-C light, while that is not the case with UV-A and UV-B light. However, with the assistance of photocatalysts, it is possible to degrade 1H-BT using UV/vis light and obtain less harmful degradation products. And lastly, natural irradiation is favourable for the degradation process due to less energy consumption and the higher proportion of irradiation. Therefore, the constant of the intrinsic reaction rate for 1H-BT was determined by which the first objective of this dissertation was achieved. Moreover, the mechanism’s degradation pathways were proposed in correlation with different intensification processes. In the FPCR setup, hydroxylation is the dominant reaction pathway of benzene cleavage with emphasized adsorption when TiO2/CNT is used. In the CPC reactor, the degradation pathway suggested nucleophilic addition reaction and triazole separation. As mentioned, the second objective of this dissertation was achieved. Finally, based on the comparative LCA, photocatalysis under natural sunlight was proposed as the optimum for scaling. Therefore, the influence of various intensification factors on solar photocatalysis application was determined. The intrinsic reaction rate constant has enabled further studies of new photocatalytic materials and their faster implementation in pilot and real-scale treatment systems. The results contributed to the 1H-BT and other pollutants treatment considerations in other aquatic systems, such as groundwaters, and the proposed degradation pathways were suggested for a better aquatic toxicity understanding. The LCA methodology was applied to study various photocatalysis intensification approaches. The most acceptable process from the environmental point of view for scale-up was proposed to be the usage of the CPC reactor under natural sunlight.

Halogenhidrin-dehalogenaze (HHDH) su enzimi koji imaju sposobnost uvođenja novih funkcionalnih skupina u molekulu, kataliziranjem reakcije otvaranja epoksida s različitim nukleofilima. Aktivno mjesto enzima može primiti više različitih neprirodnih nukleofila poput azida, cijanida i nitrita, zbog čega su enzimi privukli pažnju sintetske organske kemije. Njihova enantioselektivnost ovisi o strukturi supstrata, te često nije dovoljno visoka za sintetsku primjenu. Enzim HheB2 iz grupe B u prethodnim istraživanjima testiran je na relativno malom broju supstrata gdje je pokazao nisku enantioselektivnost, te je dugi niz godina ostao zanemaren u biokatalitičkim istraživanjima. U okviru ovog rada provedeno je opsežno ispitivanje dva divlja tipa HHDH iz skupine B: HheB iz Croynebacterium sp. soj N-1074 i HheB2 iz Mycobacterium sp. soj GP1 na nizu supstrata i nukleofila. Otkriveno je nekoliko visoko enantioselektivnih reakcija (E > 200), gdje je HheB pokazao bolju enantioselektivnost i aktivnost prema većem broju strukturno različitih supstrata u usporedbi s HheB2. Ova dva enzima dijele visoku homologiju sekvence i razlikuju se u samo četiri aminokiseline (F36I, T120A, C124Y, H125Q). Ispitivanjem mutanata HheB2 s modificiranim pojedinačnim aminokiselinama utvrđene su aminokiseline ključne za veću enantioselektivnost HheB u odnosu na HheB2. Eksperimentalni rezultati potvrđeni su i dodatno pojašnjeni računalnim analizama. Zbog izuzetne selektivnosti i aktivnosti B grupa HHDH nameće se kao odličan katalizator za sintezu velikih tercijarnih alkohola. Ispitivanjem različitih nukleofila prikazana je mogućnost sinteze enantiomerno čistih azido-alkohola i oksazolidinona, a kinetičkim mjerenjima određen je stupanj inhibicije enzima prihvaćenim nukleofilma. Halohydrin dehalogenases (HHDH) have the ability to introduce new functionalities into the molecule through the ring-opening reactions of epoxides with different nucleophiles. These enzymes draw the attention of synthetic chemistry due to their ability to accept unnatural nucleophiles such as azide, cyanide and nitrite ions. The enantioselectivity of HHDHs is substrate-dependent and not always sufficient for synthetic applications. HheB2 from B group of HHDHs has been neglected in the biocatalytic research due to the low enantioselectivity observed on a relatively small number of tested substrates. In this work, extensive screening of substrates and nucleophiles was carried out on two B wild-type HHDHs: HheB2 from Mycobacterium sp. GP1 and HheB from Corynebacterium sp. N-1074. Several highly enantioselective reactions were discovered (E > 200), with HheB showing higher enantioselectivity and activity towards larger panel of substrates compared to HheB2. These two enzymes share high sequence homology and differ by only four amino acids (F36I, T120A, C124Y, H125Q). HheB2 mutants with individual amino acids replacement are examined to determine key residues. Experimental results were confirmed and further clarified by computer analysis. Due to remarkable activity and enantioselectivity, B-group HHDHs emerged as a catalyst of choice for the synthesis of bulky tertiary alcohols. Nucleophile screening showed possibility for the synthesis of enantiomerically pure azido alcohols and oxazolidinones. Kinetic measurements were used to determine enzyme inhibition by accepted nucleophiles.

U ovome radu istražena je stabilnost, biodostupnost i dijalizibilnost polifenola pinocembrina, galangina, krizina, kavene kiseline i feniletil estera kavene kiseline u uvjetima simulirane probave in vitro (oralna i želučana faza te faza probave u tankom crijevu s dva modela: centrifugiranjem i dijalizom kroz polupropusnu membranu) na dva uzorka kontinentalnog propolisa i smjesi standarda odabranih polifenola. Različitim ekstrakcijskim postupcima i korištenjem određenih nosača istraženi su ekstrakti prikladni za oralnu primjenu te analizirani validiranom metodom tekućinske kromatografije visoke djelotvornosti uz primjenu UVdetektora s nizom fotodioda (eng. High Performance Liquid Chromatography - Photodiode Array Detection, HPLC-PDA). Primjenom 2-hidroksipropil-β-ciklodekstrina (HP-β-CD) i postupkom liofilizacije dobiven je u vodi topljivi kompleks propolis-HP-β-CD s najvećim udjelom polifenola. Rezultati analiza RP-HPLC-PDA oba uzorka kontinentalnog propolisa pokazali su stabilnost odabranih polifenola tijekom svih faza simulirane probave. Biodostupnost svih polifenola u uvjetima in vitro nakon dijalize kroz polupropusnu membranu bila je vrlo niska u odnosu na model s centrifugiranjem. Nadalje, rezultati ukazuju da u modelu s centrifugiranjem nema razlike u biodostupnosti polifenola između dva uzorka kontinetalnog tipa propolisa. Vodena suspenzija liofilizata kompleksa propolis-HP-β-CD pokazala se kao potencijalna djelatna tvar u farmaceutskim proizvodima za oralnu primjenu. In this work, the stability, bioaccessibility and dialysability of polyphenols pinocembrin, galangin, chrysin, caffeic acid and phenylethyl ester of caffeic acid were investigated after in vitro simulated digestion (oral and gastric phase and small intestine phase with two models: centrifugation and dialysis through a semi-permeable membrane) on two samples of continental propolis and standard mixture of selected polyphenols. Extracts suitable for oral administration prepared by various extraction procedures and the use of certain carriers have been investigated and analyzed by validated RP-HPLC-PDA method. Using 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) carbohydrate and by lyophilisation procedure, a propolis water-soluble complex with the highest polyphenol content was prepared. The results of RP-HPLC-PDA analysis of both propolis samples showed the stability of selected polyphenols during all phases of simulated digestion. The bioaccessibility of all polyphenols in in vitro conditions after dialysis through a semi-permeable membrane was very low compared to the centrifugation model. Furthermore, the results indicate that in the model with centrifugation there is no difference in the bioaccessibility of polyphenols between the two samples of the continental type of propolis. The aqueous suspension of the lyophilisate of the propolis-HP-β-CD complex proved to be a potential active substance in pharmaceutical products for oral administration.

Nafte se mogu vrednovati prema stabilnosti. Jedno od važnijih svojstava nafti je aromatičnost pojedinih komponenti u njezinom sastavu. Cilj ovog rada bio je istražiti međuovisnost aromatičnosti i stabilnosti uzoraka sirovih nafti. U ovom su radu primjenom spektroskopije NMR okarakterizirane sirove nafte različitog geografskog podrijetla te klasificirane prema vrijednostima relativne gustoće °API. Utvrđeno je da nafte s većim sadržajem asfaltena imaju manje vrijednosti °API. Istraživanjem povezanosti intrinzične stabilnosti nafte i udjela aromatskih vodika (aromatičnosti) iz spektara 1H NMR, utvrđeno je da uzorci manje aromatičnosti pokazuju veću intrinzičnu stabilnost. Određeni su maseni udjeli asfaltena te difuzijski koeficijenti, koji su poslužili za procjenu hidrodinamičkih radijusa i molekulskih masa komponenti u uzorku. Rezultati dobiveni taložnom titracijom i spektroskopskim metodama kombinirani su sa statističkim metodama, multivarijatnom linearnom regresijom i strojnim učenjem te je razvijen potpuno novi model za predviđanje stabilnosti nafti s iznimno dobrim faktorom korelacije za ovakve smjese. Crude oils can be classified according to their stability. The aromaticity of crude oil is one of the most important properties of oil samples. The aim of this dissertation was to investigate the correlation between the aromaticity of crude oil and the stability of crude oil samples. In this work, crude oils from different geographical origins were characterized using NMR spectroscopy and classified according to °API values. It has been shown that crude oils with a higher percentage of asphaltene have lower °API values. When investigating the correlation between the intrinsic stability of crude oil and the content of aromatic hydrogens (aromaticity) using 1H NMR, it was found that samples with lower crude oil aromaticity have higher intrinsic stability. The mass content of asphaltene and the diffusion coefficients were determined and used to estimate the hydrodynamic radii and the molecular masses. The results obtained by precipitation titration and spectroscopic methods were combined with statistical methods, multivariate linear regression and machine learning to develop a completely new model for predicting oxidation stability with an extremely good correlation factor for such mixtures.

Inhibicija butirilkolinesteraze (BChE) predstavlja novi, obećavajući pristup liječenju Alzheimerove bolesti (AB). U sklopu ove disertacije dizajnirani su i sintetizirani biskarbamati s različito supstituiranim atomima dušika karbamatnih skupina i 1-hidroksi-2-aminoetilnog lanca. Za 25 biskarbamata određena je sposobnost inhibicije ljudske BChE i acetilkolinesteraze (AChE), procijenjena je sposobnost prelaska krvno-moždane barijere pasivnim transportom, in vitro toksičnost prema jetrenim, bubrežnim i živčanim stanicama te sposobnost kelatiranja biometala Cu2+ , Zn2+ i Fe2+ . Svi ispitivani biskarbamati pokazali su vremenski ovisnu inhibiciju s konstantama brzine inhibicije od 103 − 106 mol-1 dm3 min-1 i općenito većom selektivnošću prema BChE u odnosu na AChE. Za tri biskarbamata utvrđena je mogućnost prolaska krvnomoždane barijere pasivnim transportom, dok je za njih devet ta sposobnost ograničena. Većina biskarbamata nije pokazala citotoksični učinak prema odabranim staničnim linijama, dok su svi pokazali sposobnost kelatiranja najmanje jednog od ispitanih iona biometala. Radi visoke BChE selektivnosti, netoksičnosti, sposobnosti kelatiranja biometala i prolaska krvno-moždane barijere, za daljnji razvoj kao lijekova za liječenje kasnijih stadija AB istaknula su se tri spoja (3, 9 i 26). Inhibition of butyrylcholinesterase (BChE) represents a new, promising approach to the treatment of Alzheimer's disease (AD). As part of this dissertation, biscarbamates with different substituted nitrogens of carbamate groups and 1-hydroxy-2-aminoethyl chain were designed and synthesized. For 25 biscarbamates, the ability to inhibit human BChE and acetylcholinesterase (AChE) was determined, the ability to cross the blood-brain barrier (BBB) by passive transport, in vitro toxicity to liver, kidney and neural cells and the ability to chelate biometals Cu2+, Zn2+ and Fe2+ were evaluated. All of the tested biscarbamates showed a timedependent inhibition with inhibition rate constants in 103 − 106 mol-1 dm3 min-1 range with a generally higher preference for BChE compared to AChE. For three biscarbamates it was found that they should be able to cross the BBB by passive transport, while this ability was limited for nine biscarbamates. Most of the biscarbamates did not show a cytotoxic effect against the selected cell lines. All of the biscarbamates were shown to have the ability to chelate at least one of the biometals. Due to the high BChE selectivity, non-toxicity, ability to chelate biometals and pass the BBB, three compounds (3, 9 and 26) were pointed out for further development as drugs for the treatment of later stages of AD.

Hematit (α-Fe2O3) najstabilniji je željezov oksid i važan mineral u prirodi. Zbog otpornosti na koroziju, netoksičnosti te niske cijene sinteze poželjan je materijal za različite tehnološke primjene (pigmenti, katalizatori, fotokatalizatori, fotoelektrode, elektrode za Li-ionske baterije, senzori za plinove, itd.). Svojstva uzoraka hematita i njihovi učinci u navedenim primjenama jako su ovisni o veličini i obliku čestica (morfologiji), kao i o ugradnji kationa drugih metala (Mn+) u kristalnu strukturu umjesto kationa željeza (Fe3+). Jednodimenzijske (1D) nanočestice metalnih oksida intenzivno se istražuju u zadnje vrijeme zbog svojih specifičnih fizičko-kemijskih svojstava koja mogu biti značajno poboljšana u odnosu na čestice drugih oblika. U ovom doktorskom radu priređene su 1D nanočestice hematita u prisutnosti kationa drugih metala te je istražen utjecaj tih kationa na njihovo nastajanje i strukturu te na magnetska, optička, fotokatalitička i elektrokatalitička svojstva Hematite (α-Fe2O3) is the most stable iron oxide and an important natural mineral. Due to corrosion resistance, nontoxicity, and low price of synthesis it is a desirable material for different technological applications (pigments, catalysts, photocatalysts, photoelectrodes, Li-ion battery electrodes, gas sensors, etc.). Properties of hematite samples strongly depend on morphology (particle size and shape), as well as on incorporation of other metal cations (Mn+) in the crystal structure in the place of iron cations (Fe3+). One-dimensional (1D) metal oxide nanoparticles have been intensely investigated recently due to their specific physico-chemical properties which can be significantly enhanced compared to particles of other shapes. In the present work, 1D hematite nanoparticles were synthesized in the presence of different metal cations and the influence of these cations on their formation, structure, magnetic, optical, photocatalytic and electrocatalytic properties were investigated.

Sposobnost butirilkolinesteraze (BChE) da vezanjem organofosfornih (OP) spojeva snižava njihovu koncentraciju u organizmu i time sprječava inhibiciju acetilkolinesteraze (AChE) predstavlja novi temelj terapije kod otrovanja ovim spojevima. Budući da za reaktivaciju BChE još uvijek nije pronađen učinkovit oksim, cilj ovog istraživanja bio je ispitati učinkovitost i strukturne karakteristike dvaju različitih skupina oksima u reaktivaciji BChE fosfilirane različitim organofosfatima koristeći in silico i in vitro pristup. Od 123 spojeva 1-heksil-2- ((hidroksiimino)metil) piridinijev oksim pokazao se najučinkovitijim reaktivatorom fosfilirane BChE, posebice u slučaju inhibicije ciklosarinom. Molekulskim modeliranjem pokazano je njegovo povoljno pozicioniranje u blizini fosfoniliranog katalitičkog serina uz stabilizaciju hidrofobnim interakcijama s Trp82 što omogućuje brzu nukleofilnu supstituciju fosfilne skupine s serina. Pseudokatalitički par ovog oksima i BChE u ex vivo uvjetima razgradio je stostruki suvišak ciklosarina uz povrat 70 % katalitičke aktivnosti kolinesteraza unutar 2 minute. Zaključno, pentil/heksil-temeljeni monopiridinijevi oksimi pokazali su se kao perspektivni strukturni motiv za daljnji razvoj oksima i terapije u kojoj bi učinkoviti reaktivatori s BChE omogućavali pseudokatalitičku degradaciju OP toksina u krvi. The ability of butyrylcholinesterase (BChE) to bind organophosphorus (OP) compounds lowering their concentration in the body and preventing the inhibition of acetylcholinesterase (AChE) represents a new basis for therapy in OP poisoning. Since no effective oxime has yet been found for the reactivation of BChE, the aim of this research was to examine efficiency and structural characteristics of two different oxime groups in the reactivation of BChE phosphorylated with different organophosphates using in silico and in vitro approaches. Out of 123 compounds, 1-hexyl-2-((hydroxyimino)methyl) pyridinium oxime proved to be the most effective reactivator of phosphorylated BChE, especially in the case of cyclosarin inhibition. Molecular modeling showed its favorable positioning near the phosphonylated catalytic serine stabilized by hydrophobic interactions with Trp82, which enables rapid nucleophilic substitution of the phosphyl group from serine. Pseudocatalytic pair of this oxime and BChE in ex vivo conditions degraded a hundredfold excess of cyclosarin with 70 % recovery of cholinesterase catalytic activity within 2 minutes. In conclusion, pentyl/hexyl-based monopyridinium oximes proved to be a promising structural motif for further development of oximes and therapy in which effective BChE reactivators would enable pseudocatalytic degradation of OP toxins in the blood.

U okviru ove doktorske disertacije razvijena je prva totalna sinteza marinoaziridina B, metiliranog derivata marinoaziridina A te njihovih strukturnih derivata. Kvantno-kemijskim izračunima primjenom DFT funkcionala B3LYP uz korištenje baznog skupa 6-311++G(d,p) optimizirane su strukture marinoaziridina A i B, te je ispitan solvatacijski utjecaj (kloroform) na ravnotežu para tautomera kinolin-2(1H)-ona u strukturi marinoaziridina A i B. Razvijena je enantioselektivna metoda za razdvajanje enantiomera marinoepoksida i marinoaziridina na polisaharidnim kiralnim nepokretnim fazama utemeljenim na derivatima amiloze i celuloze primjenom visokodjelotvorne tekućinske kromatografije i superkritične fluidne kromatografije. Apsolutna konfiguracija uspješno je određena primjenom računskih i kirooptičkih metoda (elektronski cirkularni dikroizam, ECD i vibracijski cirkularni dikroizam, VCD). Biološka ispitivanja marinoaziridina i odabranih derivata provedena su na tri stanične linije (MCF-7 rak dojke, H-460 rak pluća i HEK293T embrionalnog bubrega) te na bakterijskim kulturama Escherichia Coli i Staphylococcus aureus. Toksikološka ispitivanja načinjena su primjenom testa na embrijima zebra ribica. Within this dissertation, the total synthesis of marinoaziridine B, the methylated derivative of marinoaziridine A and their structural derivatives was developed for the first time. The structures of marinoaziridines A and B were optimized by quantum-chemical calculations using the DFT functional B3LYP with the use of the 6-311++G(d,p) basis set, and the solvation effect (chloroform) on the equilibrium of the tautomeric pairs of quinolin-2(1H)-on was examined. An enantioselective method was developed for the separation of enantiomers of marinoepoxide and marinoaziridine on polysaccharide chiral stationary phases based on amylose and cellulose derivatives using high performance liquid chromatography and supercritical fluid chromatography. The absolute configuration was successfully determined using computational and chiroptical methods (electronic circular dichroism, ECD and vibrational circular dichroism, VCD). Biological tests of marinoaziridine and selected derivatives were performed on three cell lines (MCF-7 breast cancer, H-460 lung cancer and HEK293T embryonic kidney) and on bacterial cultures of Escherichia Coli and Staphylococcus aureus. Toxicological tests were performed using a test on zebrafish embryos.

Ova doktorska disertacija temelji se na istraživanju (i) diskretnih i metalocikličkih spojeva, koordinacijskih polimera MoVI s nikotinhidrazonskim ligandima, (ii) soli, solvata i kokristala koordinacijskih spojeva MoVI s izonikotinhidrazonskim ligandima, (iii) organsko-anorganskih polioksomolibdatnih hibrida, i konačno (iv) metalosupramolekulskih spojeva temeljenih na različitim supstituentima i hidrazidnim komponentama liganda. Opisani su čimbenici koji utječu na njihovo nastajanje, specifični uvjeti pri kojima dolazi do nastajanja različitih izomera ili polimorfa kao i strukturne transformacije u čvrstom stanju i u otopini. Naglasak je dan na strukturnu raznolikost navedenih spojeva s obzirom na (i) protonaciju i deprotonaciju liganda, (ii) kristalizaciju različitih polimorfa; (iii) zamjenu liganada; (iv) procese samoudruživanja i kristalni rast; (v) reakcije transmetalacije i (vi) zamjene aniona. Dobiveno je 64 novih spojeva te su karakterizirani na temelju kemijske analize, difrakcijom rendgenskog zračenja na polikristalnom uzorku te spektroskopskim i termičkim metodama, a 55 spojeva identificirano je na temelju difrakcije rendgenskog zračenja na jediničnom kristalu. This doctoral thesis is based on the research of (i) MoVI discrete, metallocyclic compounds and coordination polymers with nicotinic hydrazone ligands, (ii) salts, solvates, and co-crystals of MoVI coordination compounds with isonicotinhydrazone ligands, (iii) organic-inorganic polyoxomolybdate hybrids, and finally (iv) metallosupramolecular architectures based on different ligand substituents and hydrazide components. The factors that influence their formation, specific conditions that lead to the formation of different isomers or polymorphs, as well as structural transformations in the solid state and solution, are described. Emphasis is given on the structural diversity concerning (i) the ligand protonation and deprotonation, (ii) crystallization of different polymorphs, (iii) substitutions of ligands, (iv) processes of selfassociation and crystal growth, (v) transmetalation reactions and (vi) anion exchange. 64 new compounds were obtained and characterized by chemical analysis, powder X-ray diffraction, spectroscopic and thermal methods, and 55 monocrystalline samples were identified by the single crystal X-ray diffraction method.

Li-ionski galvanski članak je složen sustav pretvorbe i pohrane energije i kao takav predmet je mnogih istraživanja s ciljem upoznavanja mehanizma litijacije i unaprjeđenja elektrokemijskih značajki. U ovom radu istraživani su anodni materijali na bazi silicija za primjenu u Li-ionskim galvanskim člancima. Sintetizirani nanostrukturirani materijali karakterizirani su morfološki i strukturno. Isti materijali ispitani su kao elektrodni materijali za Li-ionske galvanske članke testirane u obliku dvoelektrodne ćelije posebno dizajnirane i izrađene u Laboratoriju za molekulsku fiziku i sinteze novih materijala. Uzorak „saćastog“ poroznog silicija dodatno unaprijeđenog srebrovim nanočesticama pokazao je superiorna elektrokemijska svojstva visokog kapaciteta od 3333 mAh g^−1 pri 0,067 A g^−1 i 2400 mAh g^−1 pri 0,2 A g^−1. U svrhu optimiranja pripravljene su elektrode u tri različite debljine: 20, 40 i 60 μm. Metodom elektrokemijske impedancijske spektroskopije (EIS) detaljno je ispitan mehanizam vezanja Li+ iona kojom se pokazalo da je u slučaju tanjih slojeva interkalacija olakšana. Nadalje, kako bi se povećao broj ciklusa punjenja i pražnjenja, elektrolit je unaprijeđen dodatkom fluoretilen karbonata (FEC) čime je postignuto da nakon 60 ciklusa inicijalni kapacitet padne na 50 % vrijednosti, dok bez dodatka elektrolitu kapacitet već nakon 10 ciklusa padne na 20 % inicijalnog kapaciteta. In situ Ramanovom spektroskopijom praćen je proces litijacije u ovisnosti o potencijalu i vremenu čime je potvrđena promjena u morfologiji kristalnog silicija kao i stvaranje krute elektrolitne faze (SEI). Ovaj rad daje detaljan pregled cijelog procesa od priprave do testiranja materijala galvanskih članaka i umnogome pridonosi razumijevanju mehanizama vezanja i otpuštanja litijevih iona u strukturu poroznog silicija. The lithium-ion (Li-ion) cell is a complex energy conversion and storage system that has been the subject of many studies investigating the lithiation mechanism and improving its electrochemical properties. In this work, silicon-based anode materials were investigated for use in Li-ion cells. Prepared electrodes were tested as electrode materials for Li-ion cells in the form of two-electrode cell specially designed and made in our laboratory. A sample of “honeycomb” porous silicon, enhanced with silver nanoparticles, showed excellent electrochemical properties with a capacity of 3333 mAh g^−1 at 0.067 A g^−1 and 2400 mAh g^−1 at 0.2 A g^−1. To optimize the electrodes, we prepared three different electrode thicknesses: 20, 40 and 60 μm. Using electrochemical impedance spectroscopy (EIS), we investigated the intercalation mechanism of Li+ ions in detail and found that diffusion is facilitated for thinner films. To increase the number of charge and discharge cycles, we improved the electrolyte by adding fluoroethylene carbonate (FEC), which resulted in the capacity fading to 50 % of the initial capacity after 60 cycles, while without the addition of FEC the capacity dropped to 20 % of the initial capacity after 10 cycles. Using in situ Raman spectroscopy, we studied the evolution lithiation as a function of potential and time, which confirmed the change in morphology of the crystalline silicon and formation of a solid electrolyte phase (SEI). This work provides a detailed overview of the entire process from preparation to testing of galvanic cell materials and contributes significantly to the understanding of the mechanisms of alloying and dealloying lithium ions into the structure of porous silicon.

Izoleucil-tRNA-sintetaza (IleRS) katalizira nastajanje Ile-tRNAIle za ribosomsku biosintezu proteina. Postoje dva tipa IleRS, pri čemu bakterije mogu koristiti ili IleRS1 ili IleRS2 kao jedini enzim. Mala grupa organizama porodice Bacillaceae u genomu sadrži gene za obje IleRS. Rezultati ove disertacije pokazali su da iako IleRS2 omogućuje bakteriji visoku rezistenciju na mupirocin, bakterije roda Bacillus koriste isključivo IleRS1 kao glavnu sintetazu, a IleRS2 ponekad kao dodatni protein. U skladu s tim, IleRS1 je konstitutivno eksprimirana, dok je ekspresija IleRS2 inducirana mupirocinom. Između dvije IleRS bakterije Bacillus megaterium nema razlike u mehanizmima kojima se osigurava točnost sinteze Ile-tRNAIle, ali postoji razlika u brzini aminoacilacije. Sporija sinteza Ile-tRNAIle kod IleRS2 moguće je posljedica značajnije mupirocinske rezistencije u odnosu na IleRS1. Rezultati sugeriraju kako bakterije roda Bacillus koriste IleRS1 kao glavnu sintetazu prvenstveno kako bi zadovoljile potrebu za brzom translacijom i staničnom diobom što im osigurava kompetitivnu prednost u okolišu s ostalim bakterijama koje se brzo dijele. Isoleucyl-tRNA synthetase (IleRS) catalyses the formation of Ile-tRNAIle for ribosomal protein biosynthesis. Two types of IleRS exist, and bacteria can use either IleRS1 or IleRS2 as a sole housekeeping enzyme. However, a small group of organisms within family Bacillaceae have both ileS genes in their genome. This dissertation unravelled that although IleRS2 provides bacteria with a mupirocion resistance, bacteria of the genus Bacillus use exclusively IleRS1 as the main enzyme, and sometimes additionaly add IleRS2. Accordingly, IleRS1 is constitutively expressed, while IleRS2 expression is induced by mupirocin. The two IleRSs from Bacillus megaterium showed no differences in the mechanisms that ensure the accuracy of Ile-tRNAIle synthesis, but there is a difference in aminoacylation speed. The slower synthesis of Ile-tRNAIle by IleRS2 may be a consequence of mupirocin resistance found in IleRS2 compared to IleRS1. The results suggest that bacteria of the genus Bacillus use IleRS1 as the main enzyme primarily to satisfy the need for fast translation and cellular division ensuring competitive advantage in the environment with other fast-growing bacteria.

U ovom radu razvijen je postupak određivanja sadržaja selenija i odabranih elemenata u osamdeset i sedam različitih uzoraka biljnih dodataka prehrani koji su prikupljeni na hrvatskom tržištu u obliku kapsula, praha, džema ili tekućine. Metodom elektrotermičke atomske apsorpcije uz hvatanje in situ razvijenog hidrida na iridijem obloženoj grafitoj kiveti (HG-ETAAS) izmjerene su koncentracije selenija. Primjenom spektrometrije masa uz induktivno spregnutu plazmu (ICP-MS) izmjereni su sadržaji dvadeset i četiri elementa (Se, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Sb, Sr, Tl, V, Zn) u svim uzorcima. Mjerne sposobnosti dvije metode nisu se značajno razlikovale i obje metode jednako ispunjavaju zahtjeve za određivanje sadržaja selenija u biljnim dodatcima prehrani. Multivarijatnim statističkim alatima, analizom glavnih komponenata (PCA) i hijerarhijskom analizom klastera (HCA), klasificirani su dobiveni elementni profili i omogućena je vizualizacija i korelacija specifičnih elementnih profila ispitivanih uzoraka. Iz dobivenih elementnih profila potvrđeni su posebni utjecaji botaničkih, okolišnih i/ili proizvodnih uvjeta na elementni profil biljnih dodataka prehrani. In this work, the determination of selenium and selected elements in eighty-seven different herbal dietary supplements present at Croatian market in the forms of capsules, powder, tablets, jams, and liquors were analyzed. Electrothermal atomic absorption was applied with in situ trapping of generated hydride on iridium coated graphite cuvette (HG-ETAAS) for the determination of selenium. By inductively coupled plasma mass spectrometry (ICPMS), the twenty-four elements (Se, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Sb, Sr, Tl, V, Zn) were determined in all samples. Measurement capabilities of both methods were not significantly different and both methods are applicable for selenium analysis in herbal dietary supplements. By using multivariate statistical tools, principal component analysis (PCA) and hierarchical cluster analysis (HCA), elemental profiles of samples were classified. This allowed visualization and correlation of specific elemental profiles of examined samples. Distinctive features of herbal dietary supplements with peculiar influences of botanical, environmental and/or production conditions on their elemental profile were highlighted.

U okviru ove doktorske disertacije pripravljeni su, te eksperimentalnim i teorijskim metodama istraženi, novi ferocenski derivati različito supstituiranih purinskih nukleobaza s karbonilnom poveznicom između heterocikličkog i organometalnog dijela. Ferocenoil-purinski derivati 1-31 pripravljeni su reakcijom između purinskog aniona i ferocenoil-klorida pri čemu su, ovisno o C6 ili C2 supstituentima na nukleobazi, nastali N7 i N9 regioizomeri, ili isključivo N9 produkti. Pripravljeni su spojevi karakterizirani spektroskopskim i elektrokemijskim metodama (NMR, IR, UV-Vis, CV i SWV) te spektrometrijom masa (MS), ispitano je njihovo in vitro citotoksično djelovanje na L929 staničnim linijama i na humanim tumorskim staničnim linijama (A549, HepG2, PANC-1, MCF-7) te sposobnost stvaranja ROS-a kao mogućeg mehanizma citotoksičnosti. Teorijskim su pristupom uz upotrebu DFT izračuna opisana fizikalno-kemijska svojstava ferocenskih derivata nukleobaza, definirani su pogodni modeli za opis njihovih elektrokemijskih svojstva,te je objašnjen reakcijski mehanizma njihova nastanka i opisana transacilacija u organskim otapalima. Pripravljeni su spojevi elektrokemijski aktivni i stvaraju ROS acelularno i celularno. Spojevi 11 i 12 pokazali su izraženi citotoksični učinak na svim ispitanim staničnim linijama, a slijede spojevi 3 i 4, dok je spoj 26 selektivno citotoksičan za HepG2 stanice. Rezultati ovog istraživanja dobiveni povezivanjem eksperimentalnog i teorijskog pristupa, proširuju spektar pripravljenih i ispitanih redoks aktivnih ferocenoil-purinskih spojeva kao potencijalnih citostatskih agenasa. In the framework of this doctoral dissertation, new ferrocene derivatives containing variously substituted purine nucleobases with a carbonyl bond between the two parts were prepared and investigated by the experimental and theoretical methods. Ferrocenoyl-purine derivatives 1-31 were prepared by nucleophilic substitution reaction on the carbon atom of the carbonyl group of ferrocenoyl-chloride with purine nucleobase anion generated by the deprotonation with a strong base. Regioselectivity and regiospecificity of reaction were strongly influenced by the C6 or C6, C2 substituents of the purine ring. The compounds were characterized by spectroscopic, spectrometric, and electrochemical methods (NMR, IR, UV-Vis, MS, CV and SWV) and screened in an in vitro cytotoxic assay against L929 cell lines and human cancer cell lines (A549, HepG2, PANC-1, MCF-7). The ability to generate ROS was measured as a possible mechanism of cytotoxic action. Using a theoretical approach by the means of DFT calculations, the physicochemical properties of ferrocene-nucleobase derivatives were predicted and described, the reaction mechanism of their formation was resolved as well as the transacylation in DMSO. Prepared compounds showed to be electrochemically active and form ROS in both acellular and cellular media. Compounds 11 and 12 showed enhanced cytotoxic effect against all tested cell lines, followed by compounds 3 and 4, while compound 26 showed selective cytotoxic effect against HepG2 cell line. The results of this study obtained by combination of experimental and theoretical approaches, expand the range of prepared and tested redox active ferrocenoyl-purine compounds as potential cytostatic agents.

Polinezasićene masne kiseline u sastavu stanične membrane iznimno su podložne lipidnoj peroksidaciji zahvaljujući velikom broju dvostrukih veza. Lipidna peroksidacija podrazumijeva oksidativnu razgradnju lipida induciranu slobodnim radikalima te rezultira oštećenjem membrane. Smatra se da lipidna peroksidacija ima ulogu u razvoju velikog broja bolesti. Flavonoidi, prirodni polifenolni antioksidansi, istražuju se kao potencijalni lijekovi za mnoge bolesti uzrokovane oksidativnim stresom. Međutim, njihova primjenjivost ograničena je slabom topljivošću u vodenim medijima i nestabilnošću u fiziološkim uvjetima. Navedeni problem moguće je riješiti ugradnjom flavonoida u nanonosače. Zahvaljujući specifičnim magnetskim svojstvima, kao nanonosači se posebno ističu superparamagnetske nanočestice. U sklopu ove doktorske disertacije istražena je interakcija lipida i flavonoida te je uočeno da tri strukturno različita flavonoida štite cjelovitost membrane tijekom lipidne peroksidacije. Nadalje, pripravljeni su nanonosači sa superparamagnetskim svojstvima. Pokazano je da upotreba vanjskog magnetskog polja poboljšava otpuštanje flavonoida iz nanočestica. Polyunsaturated fatty acids, which are abundant in cell membranes, are susceptible to lipid peroxidation due to the large number of double bonds. Lipid peroxidation is oxidative degradation of lipids induced by free radicals which results in membrane damage. It has been correlated with numerous diseases. Flavonoids, natural polyphenolic antioxidants, are being investigated as potential therapeutics. However, their applicability is limited by poor solubility in aqueous media and instability under physiological conditions. One possible solution for the aforementioned problem is incorporation of flavonoids into nanocarriers, among which superparamagnetic nanocarriers stand out due to their exceptional magnetic properties. Within this doctoral dissertations, interaction between lipids and flavonoids has been investigated and it has been shown that three structurally different flavonoids exhibit protective behaviour of the membrane upon initiated lipid peroxidation. Moreover, superparamagnetic nanoparticles were prepared and used as nanocarriers. Drug release was improved with use of an external magnetic field.

Metodologije priprave kiralnih β,β-diaril ketona temelje se uglavnom na arilacijama 1,4- nezasićenih ketona u prisutnosti kiralnih kompleksa prijelaznih metala kao katalizatora. Iako u većini slučajeva generiraju tercijarni centar kiralnosti na β-ugljikovom atomu, u literaturi postoji nekoliko primjera gdje je moguće pripraviti tetrasupstituirani stereocentar na tom ugljikovom atomu. U sklopu ove disertacije razvijena je organokatalitička metodologija stereoselektivne priprave izoindolinonskih derivata β,β-diaril ketona s jednim kvaternim, odnosno dva vicinalna stereogena centra u prinosima 35‒98 % s visokom enantioselektivnošću (e.r. = 60:40 ‒ >99:1). Na dobivenim su produktima uspješno provedene izabrane transformacijske reakcije bez gubitka optičke čistoće. Methodologies for the enantioselective synthesis of chiral β,β-diaryl ketones are mainly based on the transition metal-catalyzed arylations of 1,4-unsaturated ketones. Most strategies for accessing these compounds yield products with tertiary stereocenters, however, there are several examples in the literature for the contruction of a tetrasubstituted (gem)-diarylalkyl center of chirality. Within this dissertation, an organocatalytic methodology for the stereoselective preparation of isoindolinone-derived β,β-diaryl ketones with one quaternary, and two vicinal stereogenic centers is developed. Products were prepared in 35‒98% yields with high enantioselectivity (e.r. = 60:40 ‒ 99:1). Obtained products successfully underwent postmodification reactions without loss of optical purity.

U ovoj disertaciji istraživani su perovskitni tanki filmovi na bazi formamidinija. Cilj rada je bio istražiti uvjete pripreme formamidinijevih perovskita, odrediti njihova strukturna, optička i električna svojstva te istražiti ulogu polivinilpirolidona kao aditiva kojim bi se postigla njihova okolišna stabilnost. Sinteza perovskitnih tankih filmova proučavana je na staklenim podlogama s ciljem razvijanja optimalnih uvjeta ponovljive sinteze funkcionalnih tankih filmova. Utvrđeni uvjeti sinteze korišteni su za pripremu perovskitnog sloja na tankim filmovima titanijeva dioksida i cinkova oksida s ciljem izrade perovskitnih fotonaponskih ćelija. Eksperimentalno dobivena fotonaponska ćelija korištena je za izradu računalnog modela simulirane fotonaponske ćelije pomoću programa SCAPS 1D. Cilj modeliranja bio je istražiti je li SCAPS prikladan program za simulaciju perovskitnih fotonaposkih ćelija te kroz računalni model procjeniti poluvodička svojstva dobivenog perovskitnog tankog filma. Polivinilpirolidon istražen je kao potencijalni aditiv perovskitnom tankom filmu sa ciljem postizanja stabilnosti filma u okolišnim uvjetima. Istraživani su uvjeti sinteze perovskitnih filmova uz dodatak polivinilpirolidona, njegov utjecaj na morfološka, optička i električna svojstva te je istraživan utjecaj aditiva na parametre fotonaponske ćelije. In this dissertation perovskite thin films based on formamidinium were investigated. The aim was to investigate formamidinium perovskite synthesis conditions, to determine their structural, optic and electronic properties and to investigate the role of polyvinylpirrolidone as an aditive for ambient stabilization of the material. The synthesis of perovskite thin films was investigated on glass substrates with the goal of developing an optimal and reproducible procedure for the preparation of functional thin films. Established synthesis conditions were used for the preparation of perovskite films on titanium dioxide and zinc oxide thin films to prepare perovskite photovoltaic cells. Obtained experimental photovoltaic devices were used to prepare a computer model of a simulated photovoltaic cell by using SCAPS 1D program with the aim to determine if SCAPS is a suitable program for the simulation of perovskite photovoltaic devices and to estimate the semiconducting properties of the perovskite thin film. Polyvinylpirrolidone was investigated as an aditive in the perovskite thin film to achieve the stability of the material in the ambient environment. The investigation included the analysis of synthesis conditions of perovskite films with the addition of polyvinylpirrolidone, its impact on the morphology, optic and electrical properties and its impact on photovoltaic parameters.

Značajan porast bakterijske rezistencije utječe na sve veću potrebu za istraživanjem i razvojem novih antibiotika. U sklopu ovog rada pripravljene su tri nove klase makrozona, konjugata makrolidnog antibiotika azitromicina i tiosemikarbazona. Tiosemikarbazoni su korišteni za kemijsku modifikaciju azitromicina na tri različita položaja. Cilj rada je priprava novih derivata makrolida sa širim spektrom biološke aktivnosti. Pripravljenim spojevima određena je biološka aktivnost in vitro na susceptibilne i rezistentne Gram-pozitivne i Gram-negativne bakterije te su istražene interakcije s biološkim receptorima. Za proučavanje interakcija primijenjena je spektroskopija NMR, cirkularni dikroizam, fluorescencijska spektroskopija i molekulsko modeliranje. Makrozoni su pokazali zadovoljavajuću biološku aktivnost, posebice na neke rezistentne bakterijske sojeve na koje azitromicin nije aktivan. Rezultati dobiveni spektroskopskim metodama i molekulskim modeliranjem ukazuju na odnos strukture i aktivnosti novih derivata azitromicina, što može poslužiti za dizajn i otkriće biaktivnijih derivata makrolida. Owing to a significant increase in bacterial resistance, a high need for discovery and development of new antibiotics has emerged. As part of this work, three novel classes of macrozones, conjugates of macrolide antibiotic azithromycin and thiosemicarbazones, were prepared. Thiosemicarbazones were used to chemically modify azithromycin at three different positions. The aim of this thesis was to prepare compounds with a wider range of biological activity including resistant bacterial strains. In vitro biological activity of the prepared compounds was determined against susceptible and resistant Gram-positive and Gram-negative bacteria, and interactions with biological receptors were investigated. Macrozones showed satisfactory biological activity, especially against some resistant bacterial strains to which azithromycin is inactive. NMR spectroscopy, circular dichroism, fluorescence spectroscopy, and molecular modeling were further used to study interactions of selected compounds with biological targets. The results obtained by spectroscopic methods and molecular modeling indicate a relationship between structure and activity of new azithromycin derivatives, which can be used for design and discovery of more active macrolide derivatives.

abezioza i dilatacijska kardiomiopatija važne su bolesti koje se nalaze u pasa, ali i ljudi. Jedna je od najčešćih komplikacija kod babezioze pasa uzrokovane protozoonom Babesia canis akutna ozljeda bubrega. Drugi je po učestalosti uzrok zatajenja srca u pasa idiopatska dilatacijska kardiomiopatija (iDCM) koja rezultira zatajenjem srca ili iznenadnom srčanom smrću zbog nastanaka aritmije. Svrha je istraživanja bila otkriti promjene u metabolomu seruma i urina pasa s promijenjenom funkcijom bubrega kod babezioze, te u metabolomu plazme pasa s iDCM-om u odnosu na zdrave pse. U istraživanju su primijenjeni neciljani i ciljani metabolomski pristup upotrebom tekućinske kromatografije spregnute sa spektrometrijom masa te metabolomska analiza temeljena na plinskoj kromatografiji spregnutoj sa spektrometrijom masa. U metabolomu seruma i urina pasa s babeziozom otkrivene su promjene povezane s oksidacijskim stresom, upalnim odgovorom domaćina, hipoksijom, anemijom i energetskim metabolizmom. U istraživanju iDCM-a identificirane su promjene u metabolomu plazme pasa i poremećaji u metaboličkim putevima koji su uključeni u razvoj iDCM-a. Babesiosis and dilated cardiomyopathy are important diseases in dogs and humans. Acute kidney injury is one of the most common complications in canine babesiosis caused with protozoa Babesia canis. The second most common cause of heart failure in dogs is idiopathic dilated cardiomyopathy (iDCM), which results in heart failure or sudden cardiac death due to arrhythmia. This study aimed to determine changes in the serum and urine metabolome of dogs with renal failure in babesiosis, and in the plasma metabolome of dogs with iDCM compared to healthy dogs. In this study, we applied an untargeted and targeted metabolomics approach using liquid chromatography coupled to mass spectrometry and gas chromatography coupled to mass spectrometry-based metabolomics. In the serum and urine samples of dogs with babesiosis were found differences associated with oxidative stress, inflammatory host response, hypoxia, anemia, and energy metabolism. We discovered changes in canine plasma metabolome and metabolic pathway disorders involved in the development of iDCM.

Da bi se istražio transport, ponašanje i raspodjela elemenata u sustavu Visovačkoga jezera analizirani su uzorci vode, sedimenata i tla koji su uzeti uzimajući u obzir geomorfološke karakteristike sustava, te dinamiku sezona i promjene protoka. Multielementna analiza napravljena je metodom spektrometrije masa visoke razlučivosti uz induktivno spregnutu plazmu. Razvijena je metoda određivanja manje istraživanih tehnološki-kritičnih elemenata (Ga, Ge, Nb, Te) u krutim okolišnim uzorcima (tla i sediment). Multielementna analiza sedimenata prevladavajućim utjecajem rijeka Krke i Čikole pokazala je značajne razlike u elementnom sastavu geoloških podloga tih rijeka. Procjenom brzine sedimentacije rekonstruirani su antropogeni pritisci koji su sve događali u prošlosti. Sedimenti u blizini nove tvornice vijaka i ispusta otpadnih komunalnih voda u Kninu pokazali su da je to i dalje potencijalni izvor zagađenja rijeke Krke ekotoksičnim elementima, ponajviše Cd, Cr i Zn, čije vrijednosti premašuju razine pri kojima se očekuje toksični učinak. Iako se rijekama Krkom i Čikolom u jezero unose ekotoksični elementi, koncentracije elemenata u sedimentima Visovačkoga jezera su općenito niske, te se taj vodeni sustav može okarakterizirati kao nezagađen ili vrlo slabo zagađen. Analizom prostornih i vremenskih raspodjela ukupnih i otopljenih elemenata u vodi tijekom nekoliko godina utvrđeno je da se pri visokim protocima najviše unose elementi pretežito vezani za čestice, dok pri niskim protocima u ljetnim mjesecima podzemne pritoke rijeke Krke čine znatan udio unosa vode u jezero. Povećane koncentracije antropogenih elemenata (Cr, Cu, Na, Pb, V) izmjerene na lokaciji gdje se Čikola ulijeva u Visovačko jezero ukazuju na antropogeno onečišćenje koje dolazi iz komunalnih voda grada Drniša. Godišnji hidrološki pronosi elemenata pokazali su da se u Visovačkom jezeru djelomično talože elementi vezani za čestice, te da osim rijeka Krke i Čikole postoje dodatni izvori unosa elemenata u jezero. The Krka River is a very clean karst water system characterised by a low level of trace elements of natural origin, which makes this system particularly sensitive to anthropogenic influences. In order to investigate the transport, behaviour and distribution of elements in the Visovac Lake system, sediment, soil and water samples were analysed, taking into account its geomorphological characteristics and the dynamics of seasonal and river flow changes. Multielement analysis was performed by high resolution inductively coupled plasma mass spectrometry technique and a method was developed for the analysis of the less studied technologically critical elements in solid samples. Sediment and water analyses identified the main anthropogenic sources and the main transport pathways of elements into this water system. The history of anthropogenic pollution by metals was reconstructed by analysing dated sediment cores. Although the input of some ecotoxic elements through the Krka and Čikola rivers was identified, their concentrations in the sediments of the Visovac Lake were generally low, so this water system can be classified as unpolluted or low-polluted with respect to metals. The analysis of the spatial and temporal distribution of total and dissolved elements in the water over a period of several years showed that the high discharges bring mainly elements bound to the particles, while during the low discharges in summer the underground tributaries of the Krka (characterised by a different elemental composition) account for a significant proportion of the water entering the lake. Increased concentrations of anthropogenic elements (Cr, Cu, Na, Pb, V) measured at the location where Čikola flows into Visovačko Lake indicate anthropogenic pollution originating from the municipal waters of the town of Drniš. The analysis of the annual hydrological fluxes of elements has shown that elements bound to particles are partially retained in the lake and that there are other sources of elements in Lake Visovac besides the Krka and Čikola rivers.

Sustavno istraživanje polimorfije organskih spojeva, a posebno djelatnih tvari, u fokusu je znanstvenih istraživanja više od 50 godina. Izuzetno su dobro istraženi fizikalni parametri koji utječu i dovode do nastanka polimorfnih formi, te je uspostavljena metodologija njihove identifikacije i karakterizacije. S druge strane, malobrojna su sustavna istraživanja kojima se nastoji spoznati u kojoj mjeri određena onečišćenja imaju utjecaj na nastanak i varijabilnost polimorfnih formi. U nakani da se potvrdi hipoteza da određena onečišćenja ili međuprodukti koji nastaju prilikom priprave djelatnih tvari mogu imati utjecaj na varijabilnost polimorfije, kao modelni spoj odabran je entakapon. Priređena je biblioteka od 11 strukturno sličnih onečišćenja te većina u literaturi opisanih polimorfnih formi entakapona. Nakon toga je provedeno istraživanje u kojem je korištenjem metoda cijepljenja i obogaćenog uzorka ispitan utjecaj vrste i strukture onečišćenja na varijabilnost polimorfije. Ustanovljeno je da je taj utjecaj veći što su spojevi sličnije građe. Na temelju dobivenih podataka potvrđena je osnovna hipoteza ovog rada. Systematic research of polymorphism of organic compounds and especially active substances, has been the focus of scientific research for more than 50 years. The physical parameters that lead to formation of certain polymorphic forms have been well researched and the methodology of identification and characterization has been established. On the other hand, there is very little systematic approach to determine the extent and impact of certain contaminants on the formation and variability of polymorphic forms. In order to confirm the hypothesis that certain impurities or intermediates used in the preparation may affect the variability of polymorphism, entacapone was selected as model compound. A library of 11 structurally related compounds and polymorphic forms of entacapone described in the literature were prepared. A study in which the influence of impurities on the variability of polymorphism was examined using seed or spike methods. This effect was found to be greater with structuraly similar compounds. Based on collected data, the basic hypothesis of this thesis was confirmed.

U ovom doktorskom radu istražen je utjecaj različitih polimera i drugih eksperimentalnih čimbenika na γ-radiolitičku sintezu magnetskih nanočestica željezovih oksida. Redukcija Fe3+ do koje dolazi γ-ozračivanjem prekursorske suspenzije praćena je spektrofotometrijski metodom s 1,10-fenantrolinom. Uz dekstran, dietilaminoetil-dekstran i dekstran sulfat moguće je postići 100 %-tnu redukciju te nastaju stabilne suspenzije magnetskih nanočestica. Uz dietilaminoetil-dekstran pri dozama 10 – 36 kGy nastaju superparamagnetske nanočestice magnetita, dok pri dozama 50 – 130 kGy nastaju magnetski nanodiskovi feroksihita. Uz dekstran sulfat nastaju getit i željezov(III) sulfat hidroksid. Uz poli(etilen-oksid) (PEO) i poli(vinil-pirolidon) nastaju magnetski polimerni gelovi ili magnetske suspenzije, a znatno slabija redukcija (~55 %) rezultira nastankom magnetita i getita, čak i pri visokim dozama (300 kGy). Stupanj umreženja i čvrstoća PEO gela rastu s dozom i koncentracijom prekursora, a do umrežavanja dolazi i preko nanočestica. Osim polimera i doze zračenja, važan utjecaj na stupanj redukcije i fazni sastav produkta imaju i koncentracija 2-propanola i Fe3+ prekursora, pH te koncentracija i molekulska masa polimera. In this thesis, the effect of different polymers and other experimental factors on the γ-radiolytic synthesis of magnetic iron oxides nanoparticles (NPs) was investigated. γ-irradiation-induced Fe3+ reduction was monitored spectrophotometrically with the 1,10-phenanthroline method. With dextran, diethylaminoethyl-dextran, and dextran sulfate colloids, it is possible to achieve a 100 % reduction and formation of stable suspensions of magnetic NPs. With DEAE-dextran, superparamagnetic magnetite NPs form in the dose range of 10 – 36 kGy, while magnetic feroxyhyte nanodiscs form in the 50 – 130 kGy dose range. With dextran sulfate, goethite and iron(III) sulfate hydroxide form. Synthesis with poly(ethylene oxide) (PEO) and poly(vinylpyrrolidone) resulted in the formation of magnetic polymer hydrogels or magnetic suspensions. Significantly lower reduction (~55 %) results in the formation of magnetite and goethite, even at high doses (300 kGy). Degree of crosslinking and strength of PEO gels improve with dose and precursor concentration, while NPs act as additional crosslinkers. Besides the polymer and dose absorbed, 2-propanol and precursor concentrations, pH, polymer concentration and molar mass also affect the reduction and phase composition of the products.

Konformacijska analiza obuhvaća široko područje istraživanja molekularnih struktura, a uz izračun odgovarajućih termodinamičkih veličina može se dobiti opis stabilnosti sustava i objašnjenje njegovih kemijskih svojstava te reaktivnosti. U okviru ovog istraživanja određeni su potpuni konformacijski prostori odabranih skupova cikličkih i acikličkih molekula metodom sustavnog pretraživanja koristeći postojeći algoritam za rigidno pretraživanje (engl. rigid scan) i novorazvijeni algoritam za prilagodljivo relaksirano pretraživanje (engl. adaptive relaxed scan) te metodom pretrage reduciranog prostora trajektorija molekularnih dinamika određenog komponentama dekompozicije tenzora drugoga i trećeg reda. Trajektorije molekularne dinamike sadrže sve steričke informacije o kemijskim strukturama molekula u istraživanom sustavu no teškoću predstavlja ogroman broj struktura koje je potrebno uzorkovati za potpunu konformacijsku analizu. Algoritam za prilagodljivo relaksirano pretraživanje omogućuje dobivanje potpunih konformacijskih prostora molekula u manje koraka čime su omogućene pretrage na znatno višim razinama teorije Conformational analysis covers a wide area of research of molecular structures, and by calculating thermodynamic parameters, a description of the stability of the system and an explanation of its chemical properties can be obtained. Within this research, complete conformational spaces for selected sets of cyclic and acyclic molecules were examined through a systematic search method using rigid scan and newly developed adaptive relaxed scan algorithm as well as dimensionality reduction method of molecular dynamics trajectories by the 2nd- and 3rd-order tensor decomposition. Molecular dynamics trajectories contain all steric information about the chemical structures of molecules in the system, but the difficulty is the large number of structures that need to be sampled for a complete conformational analysis. The adaptive relaxed scan algorithm makes it possible to obtain complete conformational spaces in fewer steps, thus enabling searches at higher levels of theory.

Izravno i selektivno uvođenje funkcionalnih skupina postignuto zamjenom inertnih veza C–H jedan je od sintetskih koraka u pripremi brojnih organskih spojeva. Ove kemijske transformacije još uvijek se pretežno oslanjaju na protokole koji uključuju upotrebu otapala, koji su često dugotrajni, zahtijevaju topljive reaktante i korištenje otrovnih otapala. U ovom su radu, kao njihova ekološki prihvatljivija alternativa, razvijeni protokoli u čvrstom stanju za aktivaciju veze C–H i halogeniranje usmjereno ligandom i katalizirano paladijevim(II) spojevima. Za ove transformacije odabrani su supstrati s donorskom skupinom koja se veže na metalni centar i dovodi ga u blizinu specifične veze C–H. Aktivacijom veze C–H nastaje reaktivna veza C–Pd koja se nakon reakcije s N-halogensukcinimidom transformira u željenu vezu C–X. Praćenjem reakcija in situ i/ili ex situ metodama te izolacijom i karakterizacijom produkata i međuprodukata pružen je uvid u mehanizam aktivacije i halogeniranja veze C–H u čvrstom stanju i otkriven snažan učinak krutih i tekućih aditiva na prirodu i reaktivnost katalitički aktivnih vrsta Pd(II) i međuprodukata. Direct and selective introduction of functional groups achieved by replacement of inert C–H bonds is one of the synthetic steps in the preparation of many organic compounds. These processes still rely heavily on solvent-based protocols, which are often time-consuming and require reactants solubility, and use toxic solvents. In this work, solid-state protocols for palladium-mediated ligand-directed C–H bond activation and halogenation were developed as a more environmentally friendly alternative. Substrates with donor group that binds to the metal center, positioning it near the specific C–H bond, were selected for these transformations. A reactive C–Pd bond formed during C–H bond activation transforms into the desired C–X bond upon reaction with N-halosuccinimide. Monitoring of the reactions by in situ and/or ex situ methods, as well as isolation and characterization of the products and intermediates, provided insight into the mechanism of C–H bond activation and halogenation in the solid-state and revealed a strong effect of the solid and liquid additives on the nature and reactivity of the catalytically active Pd(II) species and intermediates.

U ovoj doktorskoj disertaciji opisana je priprava novih derivata N-aril-3-hidroksipiridin-4-ona koji se razlikuju po strukturi supstituenata vezanih u meta- i para-položaj arilnog dijela molekule. Reakcije su provedene zagrijavanjem vodenih otopina polaznih reaktanata, maltola i meta- i para-supstituiranih anilina u autoklavu. Odabrani para-supstituirani N-aril-3- hidroksipiridin-4-oni uspješno su sintetizirani i u uvjetima mikrovalne sinteze. Pripravljeni 3- hidroksipiridin-4-oni dodatno su strukturno modificirani uvođenjem lipofilnih podjedinica u njihovu strukturu s naglaskom na adamantilnoj podjedinici. Na piranonski dio molekule 3- hidroksipiridin-4-ona adamantilna podjedinica vezana je esterskim i eterskim tipom veze dok je na meta- i para-položaj arilnog dijela molekule vezana esterskom i amidnom vezom. U disertaciji je opisana i biološka evaluacija pripravljenih spojeva. Ispitivana su antiproliferativna svojstva pripravljenih spojeva te je sustavno istražen odnos strukture i biološke aktivnosti (engl. Structure-Activity Relationship, SAR). Na temelju dobivenih rezultata izdvojeni su najpotentniji spojevi (engl. lead compound) pri čemu je uzet u obzir njihov selektivni antiproliferativni učinak. In this thesis preparation and structural modification of novel N-aryl 3-hydroxypyridin-4-one derivatives is described. Prepared compounds are distinguished by position and structure of substituent on the aryl part of the molecule. Reactions were conducted with heating of aqueous solutions of starting materials, maltol and meta- and para-substituted anilines, in autoclave. Selected para-substituted N-aryl 3-hydroxypyridin-4-ones were successfully prepared in conditions of microwave synthesis. Prepared 3-hydroxypyridin-4-ones were additionally structurally modified by incorporating lipohilic units into pyridinone structure, primarily adamantyl unit. On the pyranone part of the molecule adamantyl unit was introduced by ester and ether bond type and by using ester and amide bond in meta and para position of the aryl part of the molecule. Antiproliferative activity of prepared compounds was examined and structure-activity relationship was systematically researched. On the basis of obtained results lead compounds were singled out whereby selective activity of compounds towards tumor versus normal cell lines was considered.

U okviru doktorske disertacije razvijena je metoda za kvantitativno određivanje ostataka 27 nesteroidnih protuupalnih lijekova, kemijski različitih spojeva, tekućinskom kromatografijom ultra visoke djelotvornosti povezane s masenom spektrometrijom u uzorcima hrane životinjskog podrijetla (mlijeku, mišićnom tkivu) i uzorcima vode iz okoliša (otpadna voda). Optimiziran postupak ekstrakcije iz složenih matrica temelji se na enzimskoj hidrolizi koju slijedi ekstrakcija acetonitrilom, a dobiveni ekstrakt je pročišćen, uz istovremeno koncentriranje, ekstrakcijom na čvrstoj fazi. Validacijom metode ispitane su zadane značajke učinkovitosti koje su zadovoljile zakonski postavljene kriterije prihvatljivosti. Istraživanje je obuhvatilo i analizu realnih uzoraka s područja Republike Hrvatske, 449 uzoraka hrane životinjskog podrijetla i 96 uzoraka otpadnih voda. Kako bi se dobile informacije o toksičnosti tih spojeva koji dospijevaju u okoliš, in vitro testom na staničnim linijama ribe i ljudi ispitan je njihov citotoksični učinak. In this dissertation, a method for the quantitative determination of 27 nonsteroidal anti-inflammatory drug residues by ultra high performance liquid chromatography – mass spectrometry in food of animal origin (milk, muscle) and environmental water (wastewater) was developed. Optimised sample processing consisted of enzymatic hydrolysis and acetonitrile extraction was followed by a clean-up of the extract by solid phase extraction. By validation of the method, verified performance characteristics complied with the legally set acceptability criteria. The study also included the analysis of the real samples from regions of the Republic of Croatia, 449 samples of food of animal origin and 96 samples of wastewater. In order to obtain information on the toxicity of these compounds that are released into the environment, their cytotoxic effect was examined using in vitro test on fish and human cell lines.

Razvijene su metode analize sortnih tiola u vinu. Sortni tioli i njihovi derivati akumulirani su ekstrakcijom na čvrstoj fazi i mikroekstrakcijom na čvrstoj fazi iz para iznad otopine. Optimirani su uvjeti derivatizacije etil-propiolatom i ekstrakcije sortnih tiola. Kalibracija je provedena tehnikom dodatka standarda u kombinaciji s tehnikom izotopnog razrjeđenja deuteriranim izotopomerima kao unutarnjim standardima. Kvalitativna i kvantitativna analiza sortnih tiola provedena je vezanim sustavom plinski kromatograf i tandemni spektrometar masa s trostrukim kvadrupolom uz praćenje višestrukih reakcija. Analiti su kvantificirani i detektorom kemiluminescencije sumpora te detektirani vezanim sustavom sveobuhvatne plinske kromatografije - spektrometrije masa. Po prvi puta određene su masene koncentracije sortnih tiola u hrvatskim vinima sorte Sauvignon bijeli, koje su bile u rasponu od 6,1 ng L-1 do 135,0 ng L-1. Istražen je utjecaj dodatka antioksidansa prilikom vinifikacije na koncentraciju sortnih tiola i očuvanje arome vina. Zastupljenost sortnih tiola bila je najviša kod tretmana vina kombinacijom kalijeva metabisulfita, askorbinske kiseline i galotanina, dok su najniže koncentracije izmjerene u vinima sumporenima dvostruko nižom dozom kalijeva metabisulfita u odnosu na kontrolu. Kombinacija antioksidansa potvrđuje sinergistički utjecaj askorbinske kiseline i sumporenja vina na očuvanje sortnih tiola radi sprječavanja reakcije tiola s kinonima. Methods for the analysis of varietal thiols in wines were developed and validated. Optimization conditions for the derivatization and extraction of varietal thiols was performed. Varietal thiols or derivatives thereof were extracted by solid-phase extraction or headspace solid-phase microextraction. Calibration was performed by standard addition combined with stable isotope dilution analysis with internal standards. The developed method was used for quantification of varietal thiols in wines by gas chromatography – tandem mass spectrometry with triple quadrupole and multiple reaction monitoring, by gas chromatography – sulfur chemiluminescence detector and for detection by comprehensive gas chromatography – mass spectrometry. For the first time, the mass concentration of varietal thiols in Croatian Sauvignon Blanc wines was determined, ranging from 6,1 ng L-1 to 135,0 ng L-1. The influence of addition of various antioxidants during the vinification step on the preservation of varietal thiols was investigated. The concentrations of thiols were highest in wines treated with a blend of potassium metabisulfite, ascorbic acid and gallotannins, while being lowest for the 50 % reduced sulfurization treatment. Synergistic effect of ascorbic acid and wine sulfurization on preservation of varietal thiols and inhibition of reaction with quinones was thereby confirmed.

U ovoj disertaciji istražena je struktura i svojstva polimera 1,4-dinitrozobenzena. Razvijena je metoda sinteze ovog polimera kojom su dobiveni mikrokristali dovoljne kvalitete za određivanje molekularne i kristalne strukture. Polimer je sustavno istražen nizom spektroskopskih metoda, IR, 13C i 15N NMR, kinetika polimerizacije je ispitana u otopini, a njegova je otpornost ispitana TGA metodama u različitim atmosferama. Polazeći od dobivene molekulske i kristalne strukture izračunata je elektronska struktura, te se je pokazalo da se ovaj materijal može ponašati kao poluvodič. Budući da bi takav poluvodič načelno mogao poslužiti u razvoju molekulske elektronike, ispitano je njegovo nastajanje oligomerizacijom na uređenim površinama. Duljina tih oligomernih lanaca od prosječno 20 jedinica, kao i struktura takve površine analizirana je AFM i STM mikroskopijom. The scope of this Thesis is the detailed investigation of the structure and properties of the polymer of 1,4-dinitrosobenzene. The polymer is prepared with the newly developed method which provided the microcrystals of the satisfactory quality, such that its molecular and crystal structure is resolved by X-ray powder diffraction. The polymer is systematically analized using a series of spectroscopic methods (IR, 13C and 15N NMR), its polymerization kinetics is investigated in solution, and its robustnes is studied by thermogravimetric methods in different atmospheres. Electronic structure of the polymer is calculated starting with the obtained crystal and molecular structure. It was shown that this polymer could have properties of organic semiconductor. The ability to form regular supramolecular structures on the ordered surfaces is investigated by AFM and STM techniques. The oligomers formed on the gold surface consist from 20 monomeric units in average.

U ovome istraživanju, uvođenjem različitih (alifatskih) supstituenata na piridinski dušikov atom halogenpiridina (osobito meta izomera) pripravljeno je te strukturno, termički i spektroskopski okarakterizirano 49 novih soli protoniranih i N-alkiliranih halogenpiridina. Usporedbom halogenskih veza u strukturama N-alkil-3-jodpiridinijevih jodida utvđeno da postoji trend da što je duži ugljikovodični lanac supstituiran na dušikov atom jodpiridinskog prstena to su kraće halogenske veze C−I⋯I−. Ustanovljeno je da afinitet prema halogenskoj vezi opada s veličinom halogenidnog aniona kao akceptora, odnosno slijedi isti trend kao i u slučaju vodikove veze. Analizom raspodjele naboja na halogenpiridinijevim kationima utvrđeno je da i protoniranje i N-metiliranje halogenpiridina dovode do značajnog povećanja elektrostatskog potencijala σšupljine halogena što uvelike povećava incidenciju ostvarivanja halogenskih veza u odnosu na neutralne halogenpiridine. To čini halogenpiridinijeve katione (jodpiridinijeve posebno) prilično pouzdanim donorima halogenskih veza, te na taj način opravdava njihovu upotrebu u dizajnu i sintezi supramolekulskih struktura povezanih halogenskom vezom. In this study, 49 novel salts of halogenopyridinium cations were prepared and characterized by single crystal X-ray diffraction, and by thermal and spectroscopic analysis methods. In the crystal structures of N-alkyl-3-iodopyridinium iodides it is observed trend that longer chains as N-substituents generally leading to shorter C−I⋯I− halogen bonds. Based on the trend observed in the relative shortenings of distances of the two interactions, both halogen and hydrogen bonds seem to be decreasing in strength with the size of the halogenide anion. Inspection of the distribution of the charge on the cations revealed that both protonation and N-methylation of halogenopyridines lead to a considerable increase in the electrostatic potential of the halogen σ-hole which increase incidence of the halogen bond in the structures comprising halogenopyridinium cations (as compared to neutral halogenopyridines). This makes halopyridiniom cations (iodopyridinium in particularly) fairly reliable halogen bond donors for deliberate synthesis of halogen bonded supramolecular structures.

U ovom radu ispitana je stabilnost omjera anorganskih specija arsena As(III)/As(V) u modelnim otopinama i uzorcima prirodnih podzemnih voda s četiri lokacije u Hrvatskoj uz dodatak sljedećih konzervansa: limunska kiselina, natrijev citrat, kalijev oksalat, kalijev–natrijev tartarat i octena kiselina. Specijacijska analiza provedena je metodom voltametrije anodnog otapanja i UPLC–ICP–MS. Utvrđeno je kako kombinacija ispitanih konzervansa s octenom kiselinom uspješno stabilizira omjer specija arsena te je on u modelnim otopinama stabilan do 8 dana, dok je u uzorcima prirodnih voda stabilan 6 do 7 dana. Akutnim testom ekotoksičnosti određena je vrijednost LC50 nakon 24 h na Daphnia magna. Dobivene vrijednosti su 5,07 ppm za As(III), 10,27 ppm za As(V) i 0,58 ppm za As(III) s nanočesticama željeza. MTT testom citotoksičnosti na HepG2 staničnoj liniji određena je vrijednosti LC50 nakon 24 h. Najveća citotoksičnost određena je za As(III) uz dodatak SPIO nanočestica, dok As(V) ne inducira staničnu smrt. In this paper, the stability of inorganic arsenic species ratio As(III)/As(V) in model solutions and natural groundwater samples from four locations in Croatia was investigated. Selected preservatives were citric acid, sodium citrate, potassium oxalate, potassium sodium tartrate and acetic acid. Speciation analysis was performed by anodic stripping voltammetry method and UPLC–ICP–MS. It was shown that the combination of the tested preservatives with acetic acid stabilize the arsenic species ratio for up to 8 days in model solutions and for 6 to 7 days in natural water samples. The LC50 values determined by acute ecotoxicity test on Daphnia magna after 24 h amounted to 5.07, 10.27 and 0.58 ppm for As(III), As(V), As(III)/iron nanoparticles, respectively. Cytotoxicity was determined by MTT test on human hepatocarcinoma cell line (HepG2) after 24 h and expressed as LC50 value. The most pronounced effect was observed for As(III)/Fe nanoparticles, while As(V) was inactive.

U okviru doktorskog rada sintezirani su 2,3-disupstituirani (1 – 130) i 3-supstituirani derivati kinazolin-4(3H)-ona (131 – 136) u niskotemperaturnim eutektičkim otapalima s ciljem njihove primjene u sintezi heterocikala. Sinteze derivata kinazolin-4(3H)-ona provedene su konvencionalno, potpomognute mikrovalovima i ultrazvukom te mehanokemijskim reakcijama. Niskotemperaturna eutektička otapala za sintezu novih spojeva priređena su miješanjem kolin-klorida (ChCl) i različitih amida, karboksilnih kiselina, ugljikohidrata i alkohola u određenom molarnom omjeru. Optimiranje reakcijskih uvjeta za svaku klasu spojeva provedeno je na odabranoj modelnoj reakciji izborom najpovoljnijeg niskotemperaturnog eutektičkog otapala, volumena otapala, temperature i vremena trajanja reakcije. Pri optimiranju mehanokemijske sinteze ispitan je dodatno i utjecaj količine kuglica. Derivati 2-merkapto-3-supstituiranih kinazolin-4(3H)-ona (1 – 50) sintetizirani su u otapalu ChCl : urea reakcijom antranilne kiseline i alifatskih te aromatskih izotiocijanata konvencionalno s iskorištenjima 19 – 76 %, sintezom potpomognutom mikrovalovima u iskorištenjima 10 – 49 %, sintezom potpomognutom ultrazvukom u iskorištenjima 17 – 64 % i mehanokemijskom sintezom s iskorištenjima 48 – 88 %. 2-metil-3-supstituirani kinazolin-4(3H)-oni (51 – 87) sintetizirani su reakcijom 2-metilbenzoksazin-4-ona i aromatskih amina te hidrazida kumarina i piridin-2,6-dikarbohidrazida u otapalu ChCl : urea konvencionalno s iskorištenjima 17 – 77 %, sintezom potpomognutom mikrovalovima (10 – 41 %), sintezom potpomognutom ultrazvukom (15 – 56 %) i mehanokemijskom sintezom (45 – 87 %). Schiffove baze kinazolin-4(3H)-ona (88 – 130) sintetizirane su u otapalu ChCl : malonska kiselina reakcijom 3-amino-2-metilkinazolin-4(3H)-ona i aromatskih aldehida konvencionalno u iskorištenjima 63 – 97 %, sintezom potpomognutom mikrovalovima (39 – 68 %), sintezom potpomognutom ultrazvukom (40 – 80 %) te mehanokemijskom sintezom u visokim iskorištenjima 79 – 97 %. Trokomponentnim reakcijama antranilnih kiselina, trimetilortoformijata i aromatskih amina u otapalu ChCl : urea detektirani su 3-supstituirani derivati kinazolin-4(3H)-ona (130 – 136) u tragovima. Najbolja iskorištenja reakcija u sintezi 2,3-disupstituiranih derivata kinazolin-4(3H)-ona (1 – 130) dobivena su mehanokemijskom sintezom koju karakteriziraju najkraće vrijeme reakcije i čistoća izoliranih produkata. Zatim slijedi konvencionalna sinteza, sinteza potpomognuta ultrazvukom i s najmanjim iskorištenjem sinteza potpomognuta mikrovalovima. Korištenjem niskotemperaturnih eutektičkih otapala u sintezi smanjen je štetan utjecaj na okoliš organskih otapala i katalizatora, skraćeno je vrijeme trajanja reakcija, jednostavna je izolacija i pročišćavanje produkata te omogućeno recikliranje otapala. Strukture svih sintetiziranih spojeva potvrđene su 1H- i 13C-NMR spektroskopijom te masenom spektrometrijom. In the doctoral thesis 2,3-disubstituted (1 – 130) and 3-substituted quinazolin-4(3H)-one derivatives (130 – 136) are synthesized in deep eutectic solvents to investigate their application in the synthesis of heterocycles. Syntheses of quinazolin-4(3H)-one derivatives were performed conventionally, by microwave-assisted and ultrasound-assisted synthesis and mechanochemical reactions as well. Deep eutectic solvents for the synthesis of new compounds were prepared by mixing of choline chloride (ChCl) with various amides, carboxylic acids, carbohydrates and alcohols in a specific molar ratio. The optimization of the reaction conditions for each class of compounds was carried out on the selected model reaction by choosing the most favourable deep eutectic solvents, volume, temperature and reaction time. The influence of the amount of balls in mechanochemical synthesis was also optimized. 2-mercapto-3-substituted quinazolin-4(3H)-one derivatives (1 – 50) were synthesized in ChCl: urea deep eutectic solvent by reaction of anthranilic acids and aliphatic and aromatic isothiocyanates conventionally with yields 19 – 76%, by microwave-assisted synthesis (10 – 49%), by ultrasound-assisted synthesis (17 – 64%) and by mechanochemical synthesis (48 – 88%). 2-methyl-3-substituted quinazolin-4(3H)-one derivatives (51 – 87) were synthesized by the reaction of 2-methylbenzoxazin-4-one and aromatic amines and coumarinyl hydrazides and pyridine-2,6-dicarbohydrazide in ChCl: urea conventionally with yields 17 – 77%, by microwave-assisted synthesis (10 – 47%), by ultrasound-assisted synthesis (15 – 56%) and by mechanochemical synthesis (45 – 87%). Quinazolin-4(3H)-one Schiff bases (88 – 130) were synthesized in ChCl: malonic acid from 3-amino-2-methylquinazolin-4(3H)-ones and aromatic aldehydes conventionally with yields 63 – 97%, by microwave-assisted synthesis (39 – 68%), by ultrasound-assisted synthesis (40 – 80%) and by mechanochemical synthesis with high yields 79 – 97%. 3-substituted quinazolin-4(3H)-one derivatives (130 – 136) were detected in traces obtained by a three-component reaction of anthranilic acids, trimethyl orthoformate and aromatic amines. The best yields of the reactions in the synthesis of 2,3-disubstituted quinazolin-4(3H)-one derivatives (1 – 130) were obtained by mechanochemical synthesis, which is characterized by the shortest reaction time and the purity of the isolated products. Lower yields were obtained with conventional synthesis, ultrasound-assisted synthesis, and the lowest yields were achieved by microwave-assisted synthesis. With the use of deep eutectic solvents in the synthesis, the harmful impact of organic solvents and catalysts on the environment is reduced, the reaction time is shorter, the isolation and purification of products are simple, and the recycling of solvents is enabled. The structures of all synthesized compounds were confirmed by 1H- and 13C-NMR spectroscopy and mass spectrometry.

U okviru ovog rada pripravljena je knjižnica od 63 derivata potencijalno bioaktivnih oksima, etera i karbamata oksima, te α-acilamino-amida koji sadrže imidazolijevu ili kinuklidinijevu jezgru. Dodatno, sintetizirani su i α-acilamino-amidi koji sadrže i druge heterocikličke podjedinice (piridin, indol, tetrazol i tiofen) kako bi se dobila što raznovrsnija knjižnica novih spojeva koji do sada nisu opisani u literaturi. U sintezi spojeva primijenjene su klasične metode sinteze, mehanokemijske i sinteze potpomognutim mikrovalnim zračenjem. Varirani su uvjeti te uspoređene brzine i iskorištenja reakcija, ali i stereokemija nastalih produkata kod etera oksima. Optimirani su uvjeti za stereospecifičnu sintezu četiri etera oksima kinuklidina mehanokemijskom sintezom bez otapala i uz natrijev hidroksid kao bazu (nastaje anti izomer). Za određivanje omjera izomera etera oksima te konformera α-acilamino-amida u otopini primijenjena je spektroskopija nuklearne magnetske rezonancije. Mehanizam i stereokemija nastanka etera oksima kinuklidin-3-ona te konformacijski prostor α-acilamino-amida studirani su kvantno-kemijskim proračunima. In this work, a library of 63 derivatives of potentially bioactive oximes, oxime ethers, oximes carbamates, and α-acylamino-amides containing an imidazolium and/or quinuclidinium nucleus was prepared. In addition, α-acylamino-amides containing other heterocyclic subunits (pyridine, indole tetrazole and thiophene) were also synthesized in order to obtain the most diverse library of new compounds that have not been described in the literature so far. Classical methods of synthesis in solution, mechanochemical and microwave synthesis were used for the synthesis of compounds. The conditions were varied and the speed and yields of the reactions were compared, as well as the stereochemistry of the products formed in the case of ether oximes. The conditions for the stereospecific synthesis of four quinuclidine oxime ethers were optimized by mechanochemical synthesis without solvent and with sodium hydroxide as a base (anti isomer is formed). Nuclear magnetic resonance spectroscopy was used to determine the ratio of ether oxime isomers and α-acylamino-amide conformers in the solution. The mechanism and stereochemistry of quinuclidin-3-one oxime ether formation and the conformational space of α-acylamino-amide were studied by quantum-chemical calculations.

Istražene su korelacije strukture i magnetizma odabranih metalo-organskih mreža (MOF-ova). Opisana su magnetska svojstva Ni-MOF-74 i njegovih derivata. Rezultati pokazuju da su Ni(II) ioni u spiralnim lancima vezani feromagnetskom (FM) interakcijom ≈ 23 K dok je interakcija između lanaca antiferomagnetska (AFM) ≈ −4 K. Pri 16,8 K uzorak pokazuje fazni prijelaz u AFM stanje. Gubitak vode Ni-MOF-74 značajnije ne mijenja magnetizaciju uzorka dok amorfizacija uzrokuje spinski prijelaz Ni(II) iona iz magnetskog visokospinskog stanja S = 1 u nemagnetsko niskospinsko stanje S = 0. Istražen je i intermedijer Ni-INT, a rezultati ukazuju na postojanje slabe AFM interakcije u dimerima između lanaca. Opisana su i magnetska svojstva Cu-MOF-74 te je nađeno da postoji AFM interakcija ≈ −57 K između Cu(II) iona unutar lanca, dok je interakcija između lanaca ≈ 7,5 K. Intermedijer Cu-INT pokazuje AFM ponašanje s nešto slabijom interakcijom JNN ≈ −4 K i JIC ≈ −1,3 K. Heterometalni MOF-74 spojevi pokazuju različita AFM ponašanja ovisno o različitim sintetskim putovima. Istraženi su i porfirinski Zr-MOF-ovi s ionima Cu(II), Fe(III) i Mn(II) koordiniranim u porfirinske prstenove. Za istraživanje magnetskih svojstava navedenih spojeva korištene su metode višefrekventne elektronske paramagnetske rezonancije te magnetske susceptibilnosti. Magneto-structural correlations of selected metal-organic frameworks (MOFs) were studied. Magnetic properties of Ni-MOF-74 and its derivates were described. The results show that Ni(II) ions in helical chains are coupled ferromagnetically (FM) ≈ 23 K while the interaction between chains is antiferromagnetic (AFM) ≈ −4 K. At 16.8 K the sample shows AFM phase transition. Dehydration of Ni-MOF-74 does not significantly influence the magnetization, while amorphization induces spin-crossover from the magnetic high-spin state S = 1 to the nonmagnetic low-spin state S = 0. The intermediate Ni-INT was also investigated, and the results indicate the existence of weak dimer AFM interaction between the chains. Cu-MOF-74 was studied and it was found that there is an AFM intrachain interaction ≈ −57 K between Cu(II) ions and the interaction between chains is ≈ 7,5 K. The intermediate Cu-INT also shows AFM behavior with slightly weaker interaction JNN ≈ −4 K and JIC ≈ −1.3 K. Heterometalic MOF-74 compounds exhibt different AFM behaviour depending on different synthetic pathways. Porphyrinic Zr-MOFs with Cu(II), Fe(III) and Mn(II) ions coordinated into porphyrin rings were investigated. Multifrequency electron paramagnetic resonance and magnetic susceptibility methods were applied to study the magnetic properties of these compounds.

U ovom doktorskom radu ispitana je mogućnost primjene komercijalne fotoosjetljive smole Ceramic resin za izradu keramičkih monolitnih nosača katalizatora stereolitografijom kao jednom od tehnika aditivne proizvodnje. Specifični ciljevi uključivali su 3D-ispis monolitnih nosača različitih geometrija, razvoj i primjenu odgovarajuće tehnike nanošenja katalitički aktivnog sloja (miješani oksidi Mn, Cu, Fe i Ni) na pripremljene monolitne nosače, uključujući i različite izvedbe statičkih miješalica kao potencijalnih nosača aktivnih komponenata i testiranje njihove učinkovitosti za oksidaciju smjese aromatskih hlapljivih organskih spojeva (benzen, toluen, etilbenzen i o-ksilen - BTEX) kao i pojedinačnih modelnih BTEX komponenti. Ukupno je izrađeno 12 različitih funkcionalnih izvedbi 3D-ispisanih monolitnih nosača katalizatora, od čega 5 izvedbi u obliku statičkih miješalica. Detaljno je ispitan utjecaj različitih parametara pripreme na fizičko-kemijske, toplinske, mehaničke i katalitičke značajke različitih izvedbi strukturiranih katalizatora te utjecaj procesnih uvjeta na brzinu oksidacije aromatskih hlapljivih organskih spojeva. Rendgenskom difrakcijskom analizom utvrđeno je da se keramička faza kompozitne smole Ceramic resin sastoji od SiO2, tj. da nakon toplinske obrade dolazi do formiranja kristobalita, minerala koji je jedna od temperaturno ovisnih polimorfnih modifikacija kvarca. Elementarni sastav dodatno je potvrđen EDX analizom pri čemu je dobiveno izvrsno slaganje s literaturnim vrijednostima za istu smolu. Određena je veličina keramičkih čestica u smoli uporabom metode laserske difrakcije. Rezultati analize pokazali su da se veličina keramičkih čestica kreće u rasponu od 0,5 μm do 414 μm. Vrijednost medijana veličine čestica (d50) u populaciji iznosi 34,8 μm. Dominantna veličina keramičkih čestica u populaciji (dmode) iznosi 44,7 μm, dok Sauterov promjer (d3,2) čestica iznosi 91,5 μm. Toplinska svojstva smole Ceramic resin ispitana su provedbom simultane TGA/DTA analize. Provedeno je ispitivanje dimenzijske stabilnosti kako bi se eksperimentalno odredili korekcijski dimenzijski faktori koje treba uzeti u obzir prilikom 3D-ispisa monolitnih nosača katalizatora da bi nakon toplinske obrade ostvarili željene dimenzije. Na svim izrađenim monolitnim nosačima katalizatora izmjeren je pad tlaka u reaktorskom sustavu. Rezultati ispitivanja pokazali su gotovo zanemariv pad tlaka pri radnim uvjetima korištenim u provedenom istraživanju. Uvid u morfologiju 3D-ispisanih nosača s i bez nanesenog katalitičkog sloja i određivanje debljine nanesenog katalitičkog sloja dobiveno je upotrebom pretražne elektronske mikroskopije. Sastav katalitički najaktivnijih miješanih manganovih oksida (MnFeOx i MnCuOx) potvrđen je Ramanovom spektroskopijom. Na temelju usporedbe s rezultatima dobivenih rendgenskom difrakcijskom analizom i rendgenskom fotoelektronskom spektroskopijom uspješno je definiran sastav prisutnih miješanih metalnih oksida. Katalitički sloj nanesen je primjenom tehnike mokre impregnacije i sol-gel tehnike. Rezultati ispitivanja adhezije katalitičkog sloja na monolitnim nosačima pokazali su izvrsne rezultate s manje od 2 % gubitka mase nakon pola sata izlaganja djelovanju ultrazvuka radne frekvencije 37 kHz. Na temelju mjerenja katalitičke aktivnosti pripremljenih monolitnih katalizatora zaključeno je da je impregnacija prikladnija tehnika. Također je provedeno optimiranje kemijskog sastava katalitičkog sloja s obzirom na očekivane konverzije modelnih komponenti. Najučinkovitijom geometrijom 3D-ispisanih monolitnih nosača katalizatora pokazala se geometrija nosača ZS (zvijezda sa stijenkom) koja je sadržavala dodatne strukturne elemente (pera) s vanjske strane stijenke. 3D-ispisani monolitni nosač ZDP (zvijezda s dodatnim perima) imao je najveću geometrijsku površinu (28 cm^2) i najveću masu katalitičkog sloja (12,4 mg) te je pokazivao čak i nešto veću katalitičku aktivnost u usporedbi s aktivnošću komercijalnog (kordijeritnog) monolitnog nosača slične geometrijske površine (29 cm^2) na koji je nanesen isti katalitički sloj. Rezultati testiranja katalitičke aktivnosti pokazali su da se sve četiri BTEX komponente uklanjaju iz reakcijske smjese već pri temperaturi od 179 °C, što je od velike ekonomske važnosti s obzirom na njihovu primjenu u realnim sustavima. U završnom dijelu istraživanja provedena je analiza i modeliranje monolitnog reaktora. Za tu svrhu predložen je jednodimenzijski (1D) heterogeni model reaktora, koji uključuje kinetički model za reakciju prvog reda. Provedena je usporedba rezultata dobivenih primjenom BTEX smjese i pojedinačnih BTEX spojeva. Ocjena prihvatljivosti predloženog modela koja je provedena na temelju pripadajućih vrijednosti korijena standardnog odstupanja između eksperimentalno dobivenih i teorijski predviđenih vrijednosti pokazala je da predloženi model uspješno opisuje eksperimentalne rezultate. S obzirom na činjenicu da je 1D heterogeni model izveden na temelju pripadajućih bilanci za modelne komponente u plinskoj fazi i bilanci za modelne komponente na površini katalitičkog sloja, što odgovara fizičkoj slici procesa, zaključeno je da je predloženi model prikladan za opisivanje katalitičke oksidacije BTEX i srodnih aromatskih hlapljivih organskih spojeva uz primjenu heterogenih strukturiranih katalizatora. Rezultati prikazani u ovom doktorskom radu ukazuju na izuzetan potencijal i velike mogućnosti primjene tehnologije aditivne proizvodnje pri proizvodnji složenih izvedbi katalizatora i kemijskih reaktora. Potvrđeno je da se tehnikom stereolitografije mogu uspješno pripremiti keramički monolitni nosači koji su prema svojim katalitičkim značajkama i primjenskim svojstvima usporedivi s katalizatorima izrađenim od komercijalne kordijeritne keramike, pri čemu posebno treba istaknuti njihovu veću fleksibilnost s obzirom na proizvodnju složenih geometrijskih oblika. This dissertation investigated the possibility of using the commercially available photosensitive resin Ceramic resin for the fabrication of ceramic monolithic catalyst carriers by using stereolithography as one of the additive manufacturing techniques. Specific objectives included 3D-printing of monolithic carriers with different geometries, developing and applying a suitable technique for depositing a catalytically active layer (mixed oxides of Mn, Cu, Fe, and Ni) on the prepared monolithic carriers, including different designs of static mixers as potential active component carriers, and testing their effectiveness for oxidation of a mixture of aromatic volatile organic compounds (BTEX) and individual model components. A total of 12 different functional variants of 3D-printed monolithic catalyst carriers were prepared, 5 of which were in the form of static mixers. The influence of different preparation parameters on the physicochemical, thermal, mechanical and catalytic properties of different designs of structured catalysts and the influence of process conditions on the oxidation rate of aromatic volatile organic compounds were studied in detail. X-ray diffraction analysis showed that the ceramic phase of the ceramic resin composite was composed of SiO2, i.e., cristobalite, a mineral that is a temperature-dependent polymorphic modification of quartz, was formed after heat treatment. The elemental composition was confirmed by EDX analysis, where excellent agreement was obtained with literature values for the same resin. The size of the ceramic particles in the resin used was determined by the laser diffraction method. The results of the analysis showed that the size of the ceramic particles ranged from 0.5 μm to 414 μm. The median value of the particle size (d50) in the population is 34.8 μm. The predominant size of the ceramic particles in the population (dmode) is 44.7 μm, while the Sauter diameter (d3,2) of the particles is 91.5 μm. The thermal properties of the ceramic resin were investigated by simultaneous TGA / DTA analysis. Dimensional stability tests were performed to experimentally determine the dimensional correction factors that must be considered in 3D-printing of monolithic catalyst carriers to obtain the desired dimensions after heat treatment. The pressure drop in the reactor system was measured with all fabricated monolithic catalyst carriers. The test results showed almost negligible pressure drop under the operating conditions used in the study. Scanning electron microscopy was used to gain insight into the morphology of the 3D-printed carriers with and without an applied catalytic layer and to determine the thickness of the applied catalytic layer. The composition of the most catalytically active manganese mixed oxides (MnFeOx and MnCuOx) was confirmed by Raman spectroscopy. Comparison with the results of X-ray diffraction analysis and X-ray photoelectron spectroscopy successfully determined the composition of the mixed metal oxides present. The catalyst layer was applied by the wet impregnation technique and the sol-gel technique. The results of the study of the adhesion of the catalytic layer to monolithic carriers showed excellent results with less than 2 % weight loss after half an hour of exposure to ultrasound at an operating frequency of 37 kHz. From the measurements of catalytic activity of the prepared monolithic catalysts, it was concluded that impregnation is a more suitable method. The chemical composition of the catalyst bed was also optimized with respect to the expected conversions of the model components. The most efficient geometry of the 3D-printed monolithic catalyst carriers was found to be the geometry of the ZS carrier, which contained additional structural elements on the outside of the wall. The 3D-printed monolithic ZDP carrier had the largest geometric surface area (28 cm^2), the largest catalytic bed mass (12.4 mg), and exhibited even slightly higher catalytic activity in comparison with a commercial (cordierite) monolithic carrier with similar geometric surface area (29 cm^2) that was coated with the same catalytic layer. The results of the catalytic activity tests showed that all four BTEX components are removed from the reaction mixture already at a temperature of 179 °C, which is of great economic importance considering their application in real systems. In the last part of the research, the analysis and modeling of a monolithic reactor was carried out. For this purpose, a one-dimensional (1D) heterogeneous reactor model was proposed, which includes a kinetic model for the first-order reaction. A comparison of the results obtained with a BTEX mixture and single BTEX compounds was performed. The evaluation of the acceptability of the proposed model, performed on the basis of the corresponding root values of the standard deviation between the experimentally obtained and the theoretically predicted values showed that the proposed model successfully described the experimental results. Based on the fact that the heterogeneous 1D model is derived based on the corresponding balances for the model components in the gas phase and the balance for the model components on the surface of the catalytic layer, which corresponds to the physical picture of the process, it was concluded that the proposed model is suitable for describing the catalytic oxidation of BTEX and related aromatic volatile organic compounds using heterogeneously structured catalysts. The results presented in this dissertation demonstrate the extraordinary potential and great possibilities of the application of additive manufacturing technology in the fabrication of complex designs of catalysts and chemical reactors. It was confirmed that the stereolithography technique can successfully fabricate ceramic monolithic carriers comparable in catalytic properties and application characteristics to catalysts made of commercially available cordierite ceramics, with particular emphasis on their greater flexibility in the fabrication of complex geometric shapes.

Polibromirani difenil-eteri (PBDE) postojani su organski spojevi korišteni kao usporivači gorenja. Karakteristična su zagađivala unutarnjih prostora, a nakupljaju se u kućnoj prašini, čija je ingestija, uz prehranu, glavni put njihova unosa u ljude. Za dojenčad hranjenu ljudskim mlijekom, ono predstavlja glavni izvor izloženosti. U ovom je radu primijenjena ekstrakcija potpomognuta mikrovalovima za određivanje sedam spojeva PBDE u kućnoj prašini, a po prvi put i u uzorcima ljudskog mlijeka, uz pažljivu optimizaciju uvjeta ekstrakcije i pročišćavanja. Pročišćeni ekstrakti analizirani su plinskom kromatografijom uz detektor zahvata elektrona. Analizom 30 uzoraka ljudskog mlijeka ispitanica i prašine iz njihovih kućanstava s područja Zagreba i okolice dobivene su prve informacije o statusu onečišćenja ovim spojevima u Hrvatskoj te parametrima koji potencijalno utječu na njihove razine. Detektirani maseni udjeli spojeva PBDE bili su podjednaki onima u ostatku Europe, dok su na globalnoj razini među nižima. Prema procijenjenim dnevnim unosima spojeva PBDE, zaključeno je da ne predstavljaju rizik za zdravlje dojenčadi i majki na ovom području. Polybrominated diphenyl ethers (PBDEs) are persistent organic compounds used as flame retardants. They are typical indoor pollutants and accumulate in house dust, the ingestion of which is the most important route of exposure for humans besides diet. For breastfed infants, the main source of exposure is mother's milk. In this work, microwave-assisted extraction was used for the analysis of seven PBDEs in house dust and, for the first time, in human milk, with carefully optimized extraction conditions and clean-up. Purified extracts were analysed by gas chromatography coupled to an electron capture detector. The analysis of house dust and human milk samples from women (N = 30) living in these households in Zagreb and its surroundings provided the first information on the level of contamination with these compounds in Croatia and the parameters potentially affecting their levels. The determined mass fractions of PBDEs are similar to the rest of Europe and among the lowest in the world. The estimated daily intakes of PBDEs suggest that they do not pose a health risk to infants and mothers in the studied area.

U sklopu ove doktorske radnje razvijen je protokol koji opisuje sintezu derivata izoindolinona s triaril-supstituiranim kvaternim stereogenim centrom u organokatalitičkim uvjetima. Provedeno je stereoselektivno i regioselektivno ariliranje izoindolinona, te aza-Friedel Craftsova adicija pirola kroz položaj C3. Tako opisane transformacije katalizirane kiralnim fosfornim kiselinama uključuju širok raspon različitih nukleofila i izoindolinonskih alkohola za stvaranje kvaternog stereogenog centra s tri arilna supstituenta u odličnim prinosima i razinama enantioselektivnosti (do 98% prinosa, do 99,5:0,5 e.r.). Mehanizam stereokemijske indukcije predložen je na temelju rezultata dobivenih kvantno-mehaničkim računima i kontrolnim eksperimentima. Ispitana je primjenjivost opisanih metodologija provedbom reakcije na većoj skali i posttransformacijskom reakcijom bez gubitka optičke čistoće. An organocatalytic asymmetric protocol for the synthesis of isoindolione derivatives possessing triaryl-substituted quaternary stereogenic centers is developed. Stereoselective and regioselective arylation of isoindolinones with phenols and pyrroles at C3 position has been carried out. Described stereoselective transformations proceed smoothly with a broad range of arenes and isoindolinone alcohols in reactions mediated by chiral phosphoric acid catalyst to generate triaryl-substituted quaternary stereogenic centers in excellent yields and enantioselectivities (up to 98% yield, up to 99,5:0,5 e.r.). In the order to shed light on the mechanism of stereochemical induction, control experiments and density functional theory calculations have been performed. Applicability of such described methodologies has been investigated by conducting the postmodification and scale-up reaction without loss of optical purity in the products.

U ovoj doktorskoj disertaciji istražen je utjecaj zamjene P2O5 s WO3 i MoO3 na strukturna i električna svojstva binarnih fosfatnih te ternarnih fosfatnih stakala s konstantnim udjelom Li2O odnosno Na2O. Rezultati su pokazali značajno veću polaronsku provodnost WO3‒P2O5 stakala u odnosu na MoO3‒P2O5 stakla kao posljedicu klasteriranja WO6 oktaedara za razliku od MoO6 i MoO4 poliedra koji se uglavnom jednoliko ugrađuju u fosfatnu mrežu. Također je utvrđena važnost terminalnih kisikovih atoma u prijenosu polarona čiji nedostatak uzrokuje smanjenje električne provodnosti. U staklima s Li2O i Na2O utvrđen je učinak miješanih staklotvoraca uslijed nastajanja miješanih volframovih/molibdenovih-fosfatnih jedinica koje ubrzavaju prijenos litijevih i natrijevih iona kroz staklenu mrežu. Za razliku od stakala s Na2O, gdje je uočen maksimum DC provodnosti dodatkom WO3 i MoO3, u staklima s Li2O dobiven je porast provodnosti u cijelom području sastava zbog manjeg radijusa iona litija i posljedično njegove lakše difuzije This doctoral thesis investigates changes in structural and electrical properties occurring upon the replacement of P2O5 by WO3 and MoO3 in binary and ternary phosphate glasses containing constant Li2O and Na2O content. Significantly higher electrical conductivity of WO3‒P2O5 in comparison to MoO3‒P2O5 glasses was ascribed to the clustering of WO6 octahedra in contrast to MoO6 and MoO4 polyhedra which interconnect uniformly with phosphate network. The role of terminal oxygen atoms in polaron conduction was established and shown to be a key parameter which governs the polaron transport. Glasses containing Li2O and Na2O exhibited mixed glass former effect in which the formation of mixed tungsten/molybdenum-phosphate units facilitates the long-range mobility of lithium and sodium ions. In glasses with Na2O, the maximum in DC conductivity was observed, while glasses with Li2O showed increase in the whole compositional range due to the smaller radius of lithium ions and hence their easier diffusion.

Cerijev(IV) oksid (CeO2) jedan je od najvažnijih oksida lantanoida te se intenzivno primjenjuje u različitim područjima od poliranja, proizvodnje i skladištenja energije, zaštite okoliša do najistraživanije katalize. Svojstvo CeO2 ključno za primjenu u katalizi je sposobnost parcijalne redukcije Ce4+ u Ce3+ unutar kristalne rešetke bez narušavanja strukture pri čemu nastaju vakancije kisika. Kisikove vakancije mogu se slobodno kretati unutar kristalne rešetke te se na njih mogu lako adsorbirati molekule kisika iz okoline. Smanjenje veličine čestica te dopiranje raznim elementima s nižom valencijom i radijusom dodatno potiče stvaranje vakancija kisika te poboljšava primjenska svojstva cerijevog oksida. Među brojnim metodama sinteze nanomaterijala hidrotermalna metoda ističe se svojom jednostavnošću, ekološkom prihvatljivošću, niskom cijenom te mogućnošću dobivanja produkata visoke čistoće i homogenosti te male veličine čestica. U ovom radu hidrotermalnom metodom pripremljene su nanočestice bakrom dopiranoga cerijeva(IV) oksida (CuxCe1-xO2, x = 0, 0,1, 0,2, 0,3, 0,4 i 0,5), toplinski obrađene i temeljito analizirane različitim metodama karakterizacije nanomaterijala. Katalitička aktivnost pripremljenih nanokatalizatora ispitivana je na procesu oksidacije hlapivih organskih spojeva korištenjem plinovite mješavine benzena, toluena, etilbenzena i o-ksilena (BTEX). Provedena je i kinetička analiza rasta zrna pri izotermnim uvjetima s ciljem utvrđivanja utjecaja dodatka bakra na toplinsku stabilnost cerijeva(IV) oksida. Rendgenskom difrakcijskom analizom (XRD) utvrđeno je da do nominalnog udjela od 40 mol. % Cu ne dolazi do pojave sekundarnih faza. Veličine kristalita uzoraka bez toplinske obrade dosad su nezabilježene za bakrom dopirani cerijev(IV) oksid te iznose ispod 4 nm. Veličine čestica određene transmisijskom elektronskom mikroskopijom (TEM) u suglasju su s vrijednostima dobivenim za veličine kristalita. Masenom spektrometrijom induktivno spregnute plazme (ICP-MS), energijski razlučujućom rendgenskom spektroskopijom (EDS) i rendgenskom fotoelektronskom spektroskopijom (XPS) utvrđeno je da je stvarni udio bakra u uzorcima manji od nominalnog. Međutim, sveukupni rezultati pokazuju kako dodatak bakra ima pozitivan utjecaj na brojna svojstva CeO2, što uključuje smanjenje zabranjene zone, poboljšanje reducibilnosti i toplinske stabilnosti, te povećanje katalitičke aktivnosti. Dobiveni rezultati ukazuju na postojanje snažne interakcije između bakra i CeO2, što bi značilo je došlo do stvaranja čvrste otopine. Među pripremljenim uzorcima posebno se ističe uzorak s nominalnim udjelom bakra od 40 mol. % kao uzorak s najboljom toplinskom stabilnošću u cijelom ispitivanom području (od 300 do 700 °C), najboljom katalitičkom aktivnošću za ispitivane hlapive organske spojeve, te najvećim udjelom vakancija kisika u strukturi. Cerium(IV) oxide (CeO2) is one of the most important lanthanide oxides extensively used in various fields such as polishing, energy production and storage, environmental protection and the most researched catalysis. The key property of CeO2 for catalytic application is the ability of a partial reduction of Ce4+ to Ce3+ within the crystal lattice without the collapse of structure. During this process oxygen vacancies are formed, which can move freely within the crystal lattice and adsorb oxygen molecules from the environment. The reduction of particle size and doping with various elements with lower valence and radius further encourage the creation of oxygen vacancies and improve the properties of cerium oxide. Among many nanomaterial's synthesis methods, the hydrothermal method stands out for its simplicity, environmental friendliness, low cost and the ability to obtain products of high purity and homogeneity, as well as small particle size. In this work, nanoparticles of copper doped cerium(IV) oxide (CuxCe1-xO2, x = 0, 0,1, 0,2, 0,3, 0,4 i 0,5) were prepared by hydrothermal method, thermally treated and thoroughly characterized. The catalytic activity of the prepared nanocatalysts was investigated in the oxidation of volatile organic compounds using a gaseous mixture of benzene, toluene, ethylbenzene and o-xylene (BTEX). An isothermal grain growth kinetics analysis was also performed in order to determine the effect of copper addition on the thermal stability of cerium(IV) oxide. X-ray diffraction analysis (XRD) showed that no secondary phases occur up to the nominal share of 40 mol. % Cu. The crystallite sizes of samples without thermal treatment have not been recorded so far for copper doped cerium oxide and are below 4 nm. Particle sizes determined by transmission electron microscopy (TEM) are in agreement with the values obtained for crystallite sizes. Inductively coupled plasma mass spectrometry (ICP-MS), energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) showed that the actual copper content in the samples is lower than nominal. However, the overall results show that the addition of copper has a positive effect on a number of CeO2 properties, which includes the reduction of the band gap, improvement of reducibility and thermal stability, and an increase in catalytic activity. The obtained results indicate the existence of a strong interaction between copper and CeO2, which would mean that a solid solution was formed. Among the prepared samples, the sample with the nominal copper share of 40 mol. % stands out as the sample with the best thermal stability in the studied temperature range (from 300 to 700 °C), the best catalytic activity for the tested volatile organic compounds, and the largest share of oxygen vacancies in the structure.

Cilj rada bio je istražiti bioraspoloživost polifenola voća i utjecaj β-glukana na bioraspoloživost. Provedena je in vitro simulacija probave kožice i mesa plodova tradicionalnih kultivara i komercijalnog kultivara jabuka (Malus domestica Borkh.) te plodova crne bazge (Sambucus Nigra L.), bez i uz dodatak β-glukana. Eksperimentalni podatci (količina polifenola otpuštenih tijekom probave (ct) u ovisnosti o vremenu (t)) analizirani su kinetičkim jednadžbama. Istražen je i utjecaj polifenola na aktivnost α-amilaze i α-glukozidaze. Polifenolne skupine kožice i mesa plodova jabuka te plodova crne bazge pokazali su se kao potencijalni inhibitori α-amilaze i α-glukozidaze. Polifenoli postaju raspoloživi za apsorpciju u probavnom traktu u količinama koje su značajno manje od onih prisutnih u voću prije probave. Nakon probave u ustima, količina otpuštenih ukupnih polifenola u želudcu pokazuje značajan porast te se značajno smanjuje nakon probave u tankom crijevu. Polifenolne skupine su pokazale različita ponašanja tijekom simulirane probave. Nakon faze u ustima, količina svih polifenolnih skupina pokazala je značajan porast nakon probave u želudcu, dok su nakon probave u tankom crijevu antocijanini i flavan-3-oli potpuno nestali ili pokazali značajno smanjenje, fenolne kiseline i dihidrokalkoni pokazali značajno smanjenje, a količina flavonola bila je slična. β-glukan je smanjio količinu otpuštenih polifenola što je u nekim slučajevima bilo statistički značajno. Jednadžbe reakcija prvog i drugog reda su modificirane i prilagođene za karakteristično otpuštanje i razgradnju polifenola tijekom simulirane probave. Nelinearna regresija podataka ct u ovisnosti o t modificiranom jednadžbom prvog reda pokazala je manju standardnu grešku u usporedbi s jednadžbama reakcija drugog ili nultog reda. Simulirana probava polifenolnih skupina u želudcu i tankom crijevu slijedi kinetiku prvog reda s vremenom polureakcije unutar 10 minuta odvijanja procesa. β-glukan ima potencijalno važnu ulogu u bioraspoloživosti polifenola i količini koja dospijeva do donjih dijelova probavnog sustava što je važno za različite pozitivne bioaktivnosti polifenola. Modificirane jednadžbe reda reakcije upotrijebljene prvi puta u ovom radu mogu se primjenjivati u daljnjim istraživanjima bioraspoloživosti polifenola. This study aimed to examine the bioaccessibility of fruit polyphenols and the effect of β-glucan on polyphenol bioaccessibility. An in vitro simulation of peel and flesh digestion of fruits of traditional and commercial apple cultivars (Malus domestica Borkh.) and black elderberry (Sambucus Nigra L.) was performed, without and with the addition of β-glucan. Experimental data (amount of polyphenols released during digestion (ct) as a function of time (t)) were analyzed by kinetic equations. The effect of polyphenols on α-amylase and α-glucosidase activity was also investigated. Polyphenol classes of peel and flesh of apples and black elderberries were found as potential inhibitors of α-amylase and α-glucosidase. Polyphenols become available for absorption in the digestive system in amounts that are significantly lower than those present in fruit before digestion. After digestion in the mouth, the amount of total polyphenols released in the stomach showed a significant increase and decreased significantly after digestion in the small intestine. Polyphenolic classes showed different behaviours during simulated digestion. After the oral phase, the amount of all polyphenolic classes showed a significant increase after gastric digestion. After small intestine digestion anthocyanins and flavan-3-ols completely disappeared or showed a significant reduction, phenolic acids and dihydrocalcones showed a significant reduction, while the amount of flavonols was similar. β-glucan reduced the amount of polyphenols released, which was statistically significant in some cases. First and second order equations were modified and adjusted for the characteristic release and degradation of polyphenols during simulated digestion. Nonlinear regression of ct data as a function of t modified by the first order equation showed a smaller standard error compared to the second or zero order reactions. Simulated digestion of polyphenolic classes in the stomach and small intestine follows first-order kinetics with a half-reaction time within 10 minutes of the process duration. β-glucan plays a potentially important role in the bioaccessibility of polyphenols and the amount that reaches the lower parts of the digestive system which is important for the various positive bioactivities of polyphenols. The modified kinetic equations used for the first time in this paper can be applied in further studies of polyphenol bioaccessibility.

Pripremljeni su novi bis-aminokiselinski (Valin i Leucin) i monoaminokiselinski (Valin i Leucin) derivati fumaramida koji u svojoj strukturi na kiselinskom kraju sadrže vinilnu skupinu u obliku vinilnog estera. Novo sintetizirani derivati dobri su supramolekulski gelatori organskih otapala kao što su toluen, acetonitiril, o-, m- i p-ksileni i smjese voda/DMF i voda/DMSO. Molekule gelatora se samoudružuju nekovalentnim interakcijama, ponajviše vodikovim vezama između amidne skupine (CONH) i karboksilatne skupine (COO), tvoreći vlakna i gelsku mrežu. Iz studije morfologije vidljivo je da gelovi sadržavaju nitastu strukturu nanometarskih dimenzija isprepletenu u trodimenzionalnu mrežu. Pripremljeni derivati u svojoj strukturi sadrže reaktivne alilne skupine pogodne za provođenje reakcije polimerizacije inicirane pomoću gama ili ultraljubičastog zračenja u supramolekulskim agregatima odabranih gelova. Utvrđeno je da se reakcije polimerizacije događaju samo u gelskoj mreži te ovise o strukturi agregata odnosno blizini i orijentaciji dvostrukih veza u gelskoj mreži. Polimeri nastaju prilikom izlaganja gelova gama i ultraljubičastom zračenju u toluenu i acetonitrilu te u smjesi otapala (voda/DMF) s prijepisom strukture niti supramolekulskih gelova u polimere. Polimeri koji nastaju u otopini su amorfne prirode i ne pokazuju nitastu strukturu kao u slučaju polimerizacije u gelu. Za istraživanje i karakterizaciju supramolekulskih gelova primijenjeno je više instrumentalnih metoda, koje uključuju temperaturnu NMR i FTIR spektroskopiju, a za istraživanje morfologije gelova i polimera korištena je TEM, SEM i AFM mikroskopija. Novel bis-amino acids (Valine and Leucine) and mono-amino acids (Valine and Leucine) fumaramide derivatives have been prepared which contain a vinyl group in the form of a vinyl ester in their structure at the acid end. The newly synthesized derivatives are good supramolecular gelators of organic solvents such as toluene, acetonitrile, o, m, p-xylene and mixtures of water / DMF and water / DMSO. The gelator molecules self-assemble by noncovalent interactions, mainly by hydrogen bonds between the amide group (CONH) and the carboxyl group (COO), thus forming a gel network. Morphology studies show that the gels contain a filamentous structure of nanometer dimensions exhaustive in a three-dimensional network. The prepared derivatives in their structure contain reactive alkyl groups suitable for carrying out the polymerization reaction initiated by gamma or ultraviolet radiation in the supramolecular aggregates of selected gels. It was found that polymerization reactions occur only in the gel network and depend on the structure of the aggregate, ie the proximity and orientation of double bonds in the gel network. Polymers were formed by exposure to gamma and ultraviolet radiation in toluene, acetonitrile and water / DMF gels with transcripts of gel structure into polymers. The polymers formed in the solution do not show the structure of polymer as in the case of gel polymerization. Several instrumental methods have been applied to investigate and characterize supramolecular gels, which include temperature NMR and FTIR spectroscopy, and TEM, SEM, and AFM microscopy have been used to investigate the morphology of gels and polymers.

Kompoziti kalcijevih fosfata i titanatnih nanomaterijala, zbog komplementarnih svojstava komponenti, privlače sve veću pažnju kao napredni materijali za regeneraciju čvrstih tkiva. Dosadašnja istraživanja takvih nanokompozita većinom su usmjerena na prekrivanje nanostrukturiranih TiO2 površina kalcijevim fosfatima kako bi se poboljšala njihova bioaktivnost. Cilj ovog doktorata sustavno je istražiti biomimetsko nastajanje nanokompozita kalcijevih fosfata i titanatnih nanomaterijala u uvjetima što bližim fiziološkim. Uspoređena su dva načina sinteze nanokompozita, inkubiranjem u simuliranoj tjelesnoj tekućini te taloženjem iz suspenzije. Također je određen utjecaj biološki aktivnih molekula, albumina iz goveđeg seruma (BSA) i kitozana, na nastajanje nanokompozita. Kako bi se dobio uvid u ponašanje sintetiziranih kompozita in vivo, određeni su parametri adsorpcije i vezanja albumina iz seruma, proteina koji se pri ugradnji prvi veže na površinu implantata. Dobiveni rezultati ukazuju da je taloženje brza i svestrana metoda priprave nanokompozita kalcijevih fosfata i titanatnih nanomaterijala u kojoj se, neovisno o vrsti titanatnih nanomaterijala, ne mijenja sastav niti struktura kalcijevih fosfata. Takvi nanokompoziti pokazuju poboljšana svojstva adsorpcije proteina u odnosu na čiste kalcijeve fosfate, što ukazuje na njihov potencijal u biomedicinskim primjenama. Calcium phosphates and TiO2 nanomaterials composites are attracting attention as advanced materials for bone regeneration due to the complementary properties of the components. Current studies of such composites focus on coating TiO2 nanostructures with calcium phosphate layers to improve their bioactivity. The aim of this doctoral thesis was to systematically investigate the biomimetic preparation of nanocomposites based on calcium phosphate and titania nanomaterials under physiological conditions. Two methods of nanocomposite synthesis were compared, immersion in simulated body fluid and precipitation from a suspension. In addition, the influence of biologically active molecules, bovine serum albumin and chitosan, was determined. To evaluate the in vivo behavior of the prepared composites, the adsorption and binding parameters of serum albumin were determined, since this protein is the first to interact with the implant materials after implantation. The obtained results showed that precipitation from solution is a rapid and versatile method for preparing TiO2 and calcium phosphate composites, in which no changes in the composition or structure of the calcium phosphate phase depending on the type of titanium nanomaterials was observed. Such composites exhibit improved protein adsorption properties, indicating their potential for biomedical applications.

Cilj istraživanja bio je utvrditi postoji li razlika između vina iz kontinentalnog i primorskog područja Hrvatske, iz tri vinogradarske zone (B, CI i CII), četiri regije uzgoja (Središnja bregovita Hrvatska, Slavonija i hrvatsko Podunavlje, Hrvatska Istra i Kvarner te Dalmacija) i odabranih zaštićenih oznaka izvornosti (ZOI). U ovome su radu prikazani rezultati analize 22 makro- i mikroelementa spektrometrijom optičke emisije induktivno spregnute plazme (ICP-OES) te omjera stabilnih izotopa ugljika i kisika spektrometrijom masa omjera izotopa (IRMS) u 190 uzoraka vina, od kojih je dio proizveden konvencionalno, a dio mikrovinifikacijom. Dobiveni podaci obrađeni su metodama deskriptivne i multivarijatne statističke analize. Najveći stupanj razlikovanja vina proizvedenih u hrvatskim vinogradarskim područjima (kontinentalnom i primorskom) postignut je općom diskriminacijskom analizom (GDA) koja je pokazala točnu klasifikaciju 97,9 % svih ispitivanih uzoraka, 100,0 % autentičnih uzoraka i 84,8 % konvencionalnih uzoraka u matrici unakrsne provjere valjanosti. Najvažniji pokazatelji razlikovanja primorskog i kontinentalnog područja bili su δ¹⁸O, Co, K, Rb, Sn, Li i δ¹³C. GDA je za vina iz tri vinogradarske zone u Hrvatskoj pokazala veću razinu ispravno klasificiranih uzoraka ako su u analizi upotrijebljeni samo autentični uzorci (94,9 %) nego za sve uzorke zajedno (86,3 %) ili za konvencionalne uzorke (66,1 %) u unakrsnoj provjeri. Pri tome su najznačajnije mjerne veličine bile δ¹⁸O, Co, Rb, Li, K i Sn. Obzirom na regije uzgoja vinove loze točna klasifikacija uzoraka postignuta je za 93,6 % autentičnih vina, za 70,0 % svih vina ukupno te 53,6 % konvencionalnih uzoraka, gdje su statistički najznačajniji bili δ¹⁸O, Sn, Fe, Cu, Cr i K. GDA vina iz šest odabranih ZOI, ispravno je svrstala 93,0 % autentičnih uzoraka, 58,2 % svih uzoraka ukupno te 34,5 % konvencionalnih uzoraka, a statistički značajni bili su δ¹⁸O i Sn. Dobiveni rezultati pokazali su da odnosi između izotopnih omjera i koncentracija različitih razmatranih elemenata u kombinaciji s odgovarajućim statističkim modelom predstavljaju vrijedan alat u razlikovanju vina proizvedenih u različitim hrvatskim vinorodnim područjima, regijama, zonama i ZOI. The aim of this study was to determine whether there is a difference between wines from the continental and coastal areas of Croatia, from three wine-growing zones (B, CI and CII), four growing regions (Croatian Uplands, Slavonia and Croatian Danube, Croatian Istria and Kvarner, and Dalmatia) and selected protected designations of origin (PDO). This study presents the results of the analysis of 22 macro- and microelements by inductively coupled plasma optical emission spectrometry (ICP-OES) and the carbon and oxygen isotopes by isotope ratios mass spectrometry (IRMS) in 190 wine samples, part of which were produced conventionally and part by microvinification. The obtained data were processed by methods of descriptive and multivariate statistical analysis. The highest power for discrimination of wines produced in Croatian winegrowing areas was achieved by general discriminant analysis (GDA) showing correct classification of 97.9% of all investigated samples, 100.0% of microvinified samples and 84.8% of commercial samples in the cross-validation matrix. The most significant markers for discrimination of coastal and continental areas found by GDA were δ¹⁸O, Co, K, Rb, Sn, Li, and δ¹³C. GDA showed higher levels of correctly classified samples from three viticultural zones in Croatia if only microvinified samples were employed in the analysis (94.9%) than for all samples together (86.3%) or for commercial samples (66.1%) in the cross-validation matrix. The discrimination of viticultural zones B, CI, and CII in Croatia was achieved by δ¹⁸O, Co, Rb, Li, K and Sn. Considering the winegrowing regions, the correct classification was achieved for 93.6% of authentic wines, 70.0% of all wines and 53.6% of conventional samples, where the statistically most significant were δ¹⁸O, Sn, Fe, Cu, Cr and K. GDA for wines from selected PDOs correctly classified 93.0% of authentic samples, 58.2% of all samples and 34.5% of conventional samples, where the statistically significant were δ¹⁸O and Sn. The results obtained showed that the relationships between the isotopic ratios and concentrations of different considered elements combined with an appropriate statistical models represent a powerful tool in discrimination of wines produced in different Croatian winegrowing areas, zones, regions and PDOs.