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Chemotherapy is one of the most effective approaches used to treat cancer, a leading cause of death worldwide.[1] Ruthenium-based complexes have emerged as a powerful alternative to state-of-the-art platinum chemotherapeutics due to their reduced toxicity, higher selectivity and anti-metastatic potential.[2] Here, we employ mass spectrometry and spectroscopic techniques to characterize a novel cis-[Ru(II)(dcbpy)2Cl2] complex and investigate its interaction with cellular lipids. In addition, the cytotoxic effect and mode of action on four standard cancer cell lines, namely melanoma A375, cervical cancer HeLa and pancreas ductal adenocarcinoma MIA PaCa-2 and PANC-1, were elucidated. Our results show a dose-dependent cytotoxicity of the complex on A375, MIA PaCa-2 and PANC-1. Further, the Ru(II) complex reduces the clonogenic potential caused by G1 arrest and increases ROS production in all tested cell lines. Lipid peroxidation is also observed in HeLa and MIA PaCa-2 cells, possibly indicating ferroptosis induction. Synchrotron radiation Fourier Transform Infrared Spectroscopy was applied to study the overall interaction of a Ru-complex with cellular biomolecules, and our results demonstrated a shift in bands in the lipid fingerprint area of most cell lines, confirming the lipid rearrangement process induced by the interaction with Ru(II) complex. The complex significantly increases the percentage of apoptotic A375, HeLa and MIA PaCa-2, while a significant decrease of p62 protein, a marker for autophagy induction, is detected solely in A375 cells. The wound healing assay revealed that the Ru(II) complex reduces the metastatic potential of HeLa and MIA PaCa-2 cells by reducing their migration ability. Overall, our results indicate the existence of a general mode of action of the tested Ru(II) complex that involves growth arrest and ROS production, as well as cancer cell line-specific effects. These involve dual role trough inducing programmed cell death - apoptosis and

The treatment of infected diabetic wounds faces severe challenges due to vascular deficiencies induced by a hyperglycemia microenvironment and the extensive proliferation of drug-resistant bacteria. In this work, we developed a glucose-responsive hydrogel dressing system (CGH) with dual properties that effectively treat methicillin-resistant Staphylococcus aureus (MRSA)-infected wounds in rats and enhance wound healing. The hydrogel is synthesized using copper nanoclusters (CuNCs) cross-linked with oxidized hyaluronic acid (HA-ALD) in situ and decorated with glucose oxidase (GOx). GOx enzymatically degrades excess glucose at the wound site, generating gluconic acid and H2O2, and optimizes the limiting factors of the Fenton reaction. Decreasing pH weakens the interaction between CuNCs and HA-ALD, resulting in the release of CuNCs that catalyze the production of reactive oxygen species (ROS) by degradation of H2O2 through the Fenton reaction. This process can eradicate drug-resistant bacteria. In addition, CuNCs endowed hydrogels with excellent conductivity, thus enabling the promotion of blood vessel formation by electrical stimulation (ES), thereby facilitating tissue repair around the wound area. In conclusion, the developed novel multifunctional wound healing system can conform to irregular wound shapes, reduce glucose levels within the wound, establish a sustained sterile environment, and promote blood vessel formation through electrical stimulation, thus emerging as a highly promising and comprehensive option for effectively treating complex diabetic wounds.

Small, carbon-based nanoparticles, carbon dots (CDs), are investigated as photosensitizers (PSs) for photodynamic therapy of cancers. The results presented here show biochemical changes in cancer cells treated with surface-modified CDs, which are augmented by illumination, indicating a high potential of CDs as selective drug carriers and potent PSs. In addition, we will show that CDs produced from black carrot extract (biomass) can be exploited for image-guided therapy and be cytotoxic for cancer cells, thanks to their fluorescence properties. Finally, since biomass-fabricated CDs interact strongly with nucleic acids, they can be further developed for cell cycle sensing purposes.

In recent years researchers have developed new strategies to enhance the effectiveness of wound healing by combining nanoparticles and infra red (IR) light. For example, some studies have shown that nanoparticles can be used to enhance the absorption of near-infrared laser (NIR) light by tissues, leading to increased healing rates [1]. The influence of NIR light on proliferation, collagen production, and wound healing was tested on: keratocytes (HaCaT) and fibroblasts (MRC-5) cells that are used as model systems of human skin equivalents that comprise an epidermal and a dermal compartment of skin. Also, these cells were treated with carbon quantum dots/silver-based metal-organic framework composites (Ag-MoFs-NCDs and Ag-MoFs-SCDs), which previously showed high antibacterial activity [2], without and with laser light. Firstly, we have found the most convenient and effective CW laser intensity (16 mW/cm2) and illumination time (3 minutes), which is not too high and short enough to influence human cells' proliferation and metabolism positively. Additional chemical treatment with Ag-MoFs-NCDs and Ag-MoFs-SCDs results in a further increase in human cell viability. Our measurements showed that the proliferation index in laser-illuminated cells and cells treated with Ag-MoFs-SCDs was at the level of the untreated control. Furthermore, Ag-MoFs-SCDs treatment and laser illumination induced a mild, insignificant increase in cellular proliferation. On the other hand, Ag-MoFs-NCDs treatment led to a more pronounced, albeit not significant increase, in cellular proliferation, while Ag-MoFs-NCDs treatment combined with laser illumination significantly increased proliferation. Also, we have detected a mild change in collagen level estimated by hydroxyproline assay, which may indicate a positive outcome of combined laser illumination and treatment, taking into account that after 48 hours, a change in cell's response to the treatment could be noticed. Finally, based on migration ass

In this work, we have applied the Informational Spectrum Method (ISM) to discover a potential protein target in the HeLa cervical cancer cell line for [Pd(dach)Cl2] complex. Since Pd complexes are considered an alternative to traditionally used Pt complexes in anti-cancer therapy, it is essential to elucidate the mechanism of their action. A detailed analysis that also involves screening the known protein databases revealed the proteins of the SOSS complex as the most probable [Pd(dach)Cl2] targets. Since this protein maintains genomic stability, this result shows the potential of the Pd(II) complex as an anti-cancer drug.

Existing therapies for the treatment of pancreatic cancer are insufficiently effective and accompanied by a large number of side effects. Ruthenium complexes have shown promising antitumor properties in the previous studies 1,2 . Thus, in this investigation, anticancer effects of cis-dichlorobis (2,2'-bipyridyl-4,4'dicarboxylic acid)ruthenium(II) (Ru(II) complex) were evaluated using human pancreatic carcinoma cell lines MIA PaCa-2 and PANC-1 in vitro. Cell viability estimated with SRB assay showed significant antitumor activity of Ru(II) complex on MIA PaCa-2 (~55% of control) 48 and 72 h after treatment. On the other hand, PANC-1 cell viability was decreased only 72 h after treatment with the highest concentration of Ru(II) complex (~70% of control). Seven days after the treatment, analysis of cell survival using clonogenic assay showed a significant decrease in cell growth in both cell lines. Ru(II) complex also caused G 1 cell cycle arrest of ~13% in both cell lines. The highest percentage of apoptotic MIA PaCa-2 cells was obtained 48 h after treatment. In addition, the intracellular level of reactive oxygen species (ROS) was significantly increased, whereas cell migration was reduced in both cell lines. Summarized, Ru(II)complex demonstrates antitumor properties mediated by increased oxidative stress and also implies the antimetastatic potential, which deserves further study.

The endangered loggerhead sea turtles (Caretta caretta) are a relatively abundant sea turtle species in Madeiran waters, where they encounter various environmental stressors: from natural to anthropogenic. The physiological stress response is increased corticosterone (CS) level in the blood, achieving 2 ng/mL. Although there are various analytical methods for determining the CS concentration in turtle blood, most of them require tedious procedures for the preparation. In this work, we have tested the possibility of using matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI TOF MS) for fast screening and detection of CS in blood from a turtle captured at the coast of Madeira Island. MALDI does not require sample derivatization and is suitable for low sample volume. The linearity, precision, and limit of detection and quantification with three organic MALDI matrices were investigated in this study. The signal-to-noise ratio of the CS-derived signal was used as a parameter for quantification. Isotopically labelled corticosterone was added as a correction factor at fixed concentration to achieve better linearity and precision. Our results demonstrate that this method has the potential for quantification of CS in turtle blood. However, the lowest concentration of CS extracted from plasma that was still detectable by MALDI TOF MS was about 0.04 mg/mL, which is about ten times higher than the expected CS concentration in blood.

Platinum-based complexes represent the mainstay of treatment for various cancer types. However, their usage is often restricted by numerous side effects or intrinsic and acquired resistance. Therefore, significant research efforts have focused on developing therapeutics based on other transition metals, such as ruthenium 1,2. In this study, effects of transition metal complex, cis-dichlorobis (2,2ʹ-bipyridyl-4,4ʹ-dicarboxylic acid)ruthenium(II) (Ru(II) complex) were analyzed on A375 human melanoma and HeLa cell growth, adhesion ability andmigration. Cell viability assay indicated significant antitumor activity of Ru(II) complex on A375 (~60% of control) up to 72 h after treatment, but not on HeLa cells. However, analysis by clonogenic assay showed that growth of both cell lines was decreased 7 days after treatment. Growth inhibition was followed by G1 phase cell cycle arrest (5–10% G1 increase for A375 and 5–8% for HeLa cells compared to control). Moreover, Ru(II) complex increased adhesivity of A375 and HeLa cells by 11 and 16 % respectively and decreased cell migration, as shown by scratch assay. The obtained results indicate that the analyzed Ru(II) complex is a promising metallodrug, as itinduced growth inhibition of A375 and HeLa cells through induction of G1 arrest and decreased metastatic potential of these cells through the increase ofadhesivity and decrease of cell migration.

TiO2 prolatenanospheroids (PNSs) may be photosensitizers (PSs), which act by catalyzation of hydroxyl radical (∙OH) formation upon light illumination. ∙OH might, in turn, contribute to killing of cancer cells. On the other hand, there is great concern about toxicity in the dark of TiO2 nanoparticles in general. In this work, we have investigated the biocompatibility of TiO2 PNSs of the anatase crystal form (length between 100 and 300 nm and width 50 nm) in the dark with immune cells and light-induced cytotoxicity on several cancer cell lines. The effects of the treatment of different cell lines with several concentrations of TiO2 PNSs suspensions showed the specifics of cells’ viability and the intracellular localization. The results of in vitro studies obtained by cytotoxicity assays adjusted to individual cell lines’ metabolism point towards the biocompatibility of TiO2 PNSs at low and moderate concentrations in the dark, which neither kill the cells, nor induce activation of the immune system cells. Laser scanning confocal microscopy revealed that PNSs are taken up by cells, and insight into the intracellular distribution was obtained in this study.

INTRODUCTION: Matrix-assisted laser desorption and ionization mass spectrometry (MALDI MS) is suitable for clinical applications because of its performances. On the other hand, if organic matrices are used, analysis of small molecules (mass <1000 Da) becomes difficult due to a high number and intensity of matrix –related signals. Certain physiologically important molecules, such as hormones, carbohydrates, drugs, and others, belong to the small molecule group. Application of TiO2 nanoparticles as substrates for surface-assisted laser desorption and ionization (SALDI) MS is, in these cases, promising tool. OBJECTIVES: To test the suitability of TiO2 nanoparticles with various sizes and shapes as substrates for SALDI MS of various classes of small biologically-relevant molecules. METHODS: The following TiO2 nanoparticles are prepared: colloidal nanoparticles (NPs, round, diameters of 5 nm), prolate nanospheroids (PNSs, 40-50 nm length) and nanotubes (NTs, approximately 100 nm long, 10 nm diameter). Samples (amino acids, steroid hormons, vitamins, carbohydrates) at various concentration were analyzed in positive and negative mode, whereas reproducibility and day-to-day repeatability was tested by ANOVA statistical analysis. RESULTS: By tested organic matrices, 63% of samples could not be detected, whereas by using any of nanoparticles, only 33% of analytes were not detectable. The spectra acquired with TiO2 nanoparticles, were characterized by lower number of well defined signals, which did not overlap with the signals from analytes. Analyte signals are simple, and the number of analyte-generated adducts is low when TiO2 substrates are used. Moreover, in some cases, also molecular ions could be detected. Generally, spectra were better reproducible when acquired with nanoparticles compared to organic matrices, as judged by the standard deviations in the signal-to-noise ratio (standard deviations are smaller when nanoparticles are used). In that sense, PNSs demonstrated

Sinteza i primena kompleksa prelaznih metala u lečenju kancera je predmet istraživanja velikog broja naučnika. Potreba za razvojem novih citostatika proizilazi iz želje da se prevaziđu nedostaci već postojećih, kao što su rezistencija, toksičnost i uzak terapeutski opseg (aktivnost protiv malog broja tipova tumora). Tako se pored kompleksa platine, i dalje najčešće korišćenih citostatika u kliničkoj praksi, razvila čitava serija novih kompleksa redizajniranjem već postojećih izmenom liganada i/ili izmenom centralnog metalnog jona. Posebno su se izdvojili kompleksi rutenijuma zbog manje toksičnosti, aktivnosti na metastazama i tumorima na kojima su dotadašnji citostatici bili neaktivni, a neki od njih su pokazali aktivnost tek kada se ozrače svetlošću odgovarajuće talasne dužine i potencijal za primenu u fotodinamičkoj terapiji. Uprkos razvoju novih generacija citostatika s poboljšanim karakteristikama, kao problem ostaje kontrola postizanja maksimalne koncentracije leka u tumorskom tkivu. Na putu do ciljnog, tumorskog tkiva i ciljnih biomolekula, lek interaguje i s brojnim drugim biomolekulima što za posledicu može imati toksičnost, pojavu rezistencije, inaktivaciju leka i smanjenje njegove efektivne koncentracije na željenom mestu dejstva. Potreba za prevazilaženjem ovog problema dovela je do brzog razvoja nosača za lekove. Njihova uloga je da vežu ili inkapsuliraju lek, nose ga do tumorskog tkiva sprečavajući njegovu interakciju s okolnim biomolekulima i zatim ga otpuste, aktivnim ili pasivnim mehanizmom, u ciljnom tumorskom tkivu. Cilj upotrebe ovakvih sistema je smanjenje štetnog dejstva leka na zdravo tkivo, mogućnost kontrole doziranja leka tj. postizanje njegove optimalne koncentracije u tumorskom tkivu, a samim tim i postizanje veće efikasnosti terapije. Nosači koji se testiraju za mogućnost primene u kontrolisanoj i ciljanoj dostavi medikamenata su uglavnom na bazi organskih i neorganskih nanomaterijala, međutim mali broj njih je u kliničkoj upotrebi (lipoz, A significantly rising interest in the design and use of metal complexes for cancer treatment is currently observed in the area of scientific inquiry. There has been a growing demand for development and improvement of metal-based compounds used in routine clinical practice in order to overcome disadvantages and limitations such as resistance, toxicity and narrow spectrum of activity (activity against a small number of tumor types). Beside platinum complexes, the leading agents in clinical use, many more metal-based compounds have been synthesized by redesigning the existing chemical structure through ligand substitution and/or central metal ion switching. Among them ruthenium complexes have been investigated as one of the most promising candidates because they shown less toxicity, significant activity against cancer metastases, and activity on tumors that were resistant to a variety of standard chemotherapeutic agents. Moreover, some of them are light sensitive drugs i.e. their functions is triggered once they are activated by light of a specific wavelength which make them promising candidates for photodynamic therapy. Despite fast development of new generation of cytostatics with better characteristics, there are still areas where substantial improvements need to be made. One such area is achievement of a maximum concentration of the drug on tumor site. Once the drug enters the systemic circulation, it could face a number of challenges. Drug could react with nontarget biomolecules on its way to target biomolecules in tumor tissue which could cause severe side effects such as toxicity, resistance, inactivation of the drug and reduction of its effective concentration at the target tumor site. One way to solve these problems is the development of drug delivery systems which consist of drug and drug carrier. Role of drug carriers is to bind or encapsulate the drug, prevent its interaction with non-target biomolecules, to carry the drug to the target tumor tissue and th

This paper presents optimization of matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometer (MS) instrumental parameters for the analysis of chloro(2,2 , 2 -terpyridine) palladium(II) chloride dihydrate complex applying design of experiments methodology (DoE). This complex is of interest for potential use in the cancer therapy. DoE methodology was proved to succeed in optimization of many complex analytical problems. However, it has been poorly used for MALDI-TOF-MS optimization up to now. The theoretical mathematical relationships which explain the influence of important experimental factors (laser energy, grid voltage and number of laser shots) on the selected responses (signal to noise - S/N ratio and the resolution - R of the leading peak) is established. The optimal instrumental settings providing maximal S/N and R are identified and experimentally verified.

In this work it has been shown that both the laser desorption/ionization mass spectrometry (LDI MS) and the matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) are the simple and quick methods for determination of relative natural isotopic distribution of lead. The analysis of metal salts with these approaches does not require any time-consuming preparation of samples: a single run can take only a minute, and numerous information can be obtained. Results obtained in this work show that chosen matrix has no negative effect on quantitative determination of lead isotopes and support once more the applicability of MALDI TOF MS for lead isotope distribution determination in the sample and accurate data are obtained. Additionally, the generation of PbnOn and PbnOn-1 (n: 2-6) clusters have been successfully achieved in the positive mode, using the both LDI and MALDI methods. All stoichiometries were confirmed using isotopic pattern modelling.

Approximately 13 million of new cancer cases are diagnosed every year, and the mortality rate is projected to rise, with an estimation of 13.1 million deaths in 2030 [1]. The conventional cancer treatments such as chemotherapy, radiotherapy and surgery suffer from serious drawbacks that hamper patients’ healing and recovery: radiation therapy is limited by the cumulative radiation dose,chemotherapy is frequently associated with systemic side-effects, while rather high recurrence rate is associated with surgical resection of tumors. Photodynamic therapy, which implies combined use of a photosensitising medicament and low-intensity light to cause selective damage to the target tissue, is an alternative tumor-ablative, function-sparing and costeffective oncologic approach [2]. Usually, medicaments are delivered to diseased tissues by different types of nanoparticle (NP) carriers. The light-induced medicament activation is based on the intrinsic optical properties of a medicament carrier and a medicament itself. In most cases, a NP-based medicament carrier or a medicament itself acts as photosensitizers [PSs], by triggering the free radical reactions in cells leading eventually to the cell death. The most PSs are characterized by high lipophilicity, and due to that, different encapsulation strategies have been explored to protect the hydrophobic PS from the aqueous environment. We used TiO2 NPs for medicament carriers because of their availability, non-toxicity, stability and possibility of surface modification. On the other hand, Ru(II)(dcbpy)2Cl2 complex, that belongs to the second generation of metallodrugs, can be easily attached to the TiO2 surface via carboxyl groups [3], while central metal ion remains free for the interaction with biomolecules. Additionally, this system has genotoxic effect on melanoma cells [4]. The aim of the present study was to modify the nanocomposite system (NCS) based on the Ru complex and TiO2 NPs in order to increase the cellular uptake

U ovom radu, matematička metoda Dizajn eksperimenta (eng. Design of Experiment, DoE) korišćena je za optimizaciju instrumetalnih parametara masenog spektrometra sa laserskom desorpcijom i jonizacijom pomoću „matriksa“ i sa analizatorom na bazi vremena preleta (MALDI TOF MS), a za analizu metalnih kompleksa. Ulazni parametri DoE metodologije bili su intenzitet lasera, napon na „gridu“ i broj impulsa lasera, dok su kao izlazni parametri od interesa bili odnos signal/šum i rezolucija. Različite vrednosti ulaznih parametra (njihovi nivoi) definisane su na osnovu dobijenih preliminarnih eksperimenata. Nakon utvrđivanja ulaznih i izlaznih parametara DoE eksperiment je izveden primenom Box-Behnken-ove metode. Teorijski predviđene vrednosti za dobijanje kvalitetnog masenog spektra metalnog kompleksa (snaga lasera-1220 W, napon „grida“-79 V i broj impulsa lasera-360) su eksperimentalno potvrđeni., In this work Design of Experiment mathematical methodology (DoE) was used for optimization the instrumental parameters of matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometer (MS) for the analysis of metal complex. The input factors in DoE methodology were laser intensity, grid voltage and number of laser shots, while the output response of interest were signal-to-noise ratio and resolution. The different values of input factors (their level) are defined according to the results obtained in preliminary experiments. After the identification of input factors and responses of interest the DoE experimental plan is created using Box-Behnken methode. Theoretically predicted values for obtaining high-quality mass spectra of metal complex (laser power – 1220 W, grid voltage – 79 V and number of laser shots – 360) are experimentally confirmed.

U ovom radu, matematička metoda Dizajn eksperimenta (eng. Design of Experiment, DoE) korišćena je za optimizaciju instrumetalnih parametara masenog spektrometra sa laserskom desorpcijom i jonizacijom pomoću „matriksa“ i sa analizatorom na bazi vremena preleta (MALDI TOF MS), a za analizu metalnih kompleksa. Ulazni parametri DoE metodologije bili su intenzitet lasera, napon na „gridu“ i broj impulsa lasera, dok su kao izlazni parametri od interesa bili odnos signal/šum i rezolucija. Različite vrednosti ulaznih parametra (njihovi nivoi) definisane su na osnovu dobijenih preliminarnih eksperimenata. Nakon utvrđivanja ulaznih i izlaznih parametara DoE eksperiment je izveden primenom Box-Behnken-ove metode. Teorijski predviđene vrednosti za dobijanje kvalitetnog masenog spektra metalnog kompleksa (snaga lasera-1220 W, napon „grida“-79 V i broj impulsa lasera-360) su eksperimentalno potvrđeni., In this work Design of Experiment mathematical methodology (DoE) was used for optimization the instrumental parameters of matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometer (MS) for the analysis of metal complex. The input factors in DoE methodology were laser intensity, grid voltage and number of laser shots, while the output response of interest were signal-to-noise ratio and resolution. The different values of input factors (their level) are defined according to the results obtained in preliminary experiments. After the identification of input factors and responses of interest the DoE experimental plan is created using Box-Behnken methode. Theoretically predicted values for obtaining high-quality mass spectra of metal complex (laser power – 1220 W, grid voltage – 79 V and number of laser shots – 360) are experimentally confirmed.

Lečenje kancera u današnje vreme uključuje primenu različitih terapija koje se uglavnom zasnivaju na primeni kompleksa prelaznih metala. Kada se razmatraju nove strategije u lečenju kancera, ističe se fotodinamička terapija. Ovaj vid terapije koristi svetlo kao aktivator leka ili nosača leka na mestu obolelog tkiva. Uzimajući u obzir navedeno, testirali smo potencijal prethodno sintetisanog fotoaktivnog nanokompozitnog sistema i njegovih komponenti za primenu u fotodinamičkoj terapiji. Pomenuti sistem se sastoji od nanočestica TiO2 kao nosača leka i kompleksa [Ru(II)(dcbpy)2Cl2], kao potencijalnog citostatika, vezanog za površinu nanočestica. Rutenijumov kompleks iskazuje svoje citotosično delovanje vezivanjem za ciljne biomolekule, dok dosač, TiO2, vezujući kompleks može smanjiti njegovu reaktivnost sa zdravim ćelijama dok ne dođe do tumorskog tkiva. Pomenuti nanokompozitni sistem i njegove komponente su testirane na ćelijama melanoma. Rezultati ukazuju na to da dejstvom UV svetla, nakon tretmana sa obe komponente sistema (kompleksom i TiO2) dolazi do značajnog smanjenja u broju tumorskih ćelija, dok je nanokompozitni sistem pokazao sinergistički efekat i dovodio do smanjenja broja tumorskih ćelija ispod 50%. Stoga, ovaj sistem ostavlja mesta za dalja izučavanja jer pruža mogućnost razvoja efiksnije terapije u kojoj bi doziranje leka bilo kontrolisanano svetlom., The treatment of cancer involves different therapies mainly based on transition metal complexes. When exploring new strategies for the treatment of cancer, one possibility is the use of photodynamic therapy. Photodynamic therapy utilizes light to activate a drug or a drug/carrier system when they are localized in the tumor tissue. Therefore, we have tested the potential of previously synthesized photoactive nanocomposite system and its components as a candidate for photodynamic therapy. The nanocomposite system consists of TiO2 nanoparticles as drug/carrier and ruthenium.complex [Ru(II)(dcbpy)2Cl2] bound to its surface as a potential antitumor drug. This Ru complex have been shown to exert cytotoxic effect through binding to target biomolecules, while TiO2 carrier can serve to minimize side reactivity in the bloodstream and healthy cells until it reaches tumor cells. The nanocomposite system and its components are successfully applied on melanoma tumor cell lines. It was demonstrated that the illumination by UV light, after treatment either with Ru-complex or TiO2 nanoparticles significantly decreases melanoma cell survival rate, while NCS shown synergistic effect and have reduced the number of melanoma cells under 50%. Hence, this system might be of interest from the standpoint of development of more efficient, light controllable drug delivery approaches.

U ovom radu, uporedili smo masene spektre vitamina E i A dobijene laserskom jonizacijom i desorpcijom (LDI), sa organskim matricama (DHB, 9AA, CHCA i THAP) i pomoću supstrata na bazi titan dioksid (TiO2) nanokristala različitih oblika i dimenzija (koloidne nanočestice, prolatni nanosferoidi i nanotube) jer ovi faktori utiču na procese desorpcije i jonizacije. Za procenu ponovljivosti merenja unutar jednog dana i između dana LDI, MALDI i SALDI TOF tehnika korišćena je Excel alatka (ANOVA). Homogenost distribucije ko-kristala (smeše) uzorka/matrice (supstrata) na M(S)ALDI pločici je izražena kao srednja vrednost koeficijenta varijacije serije merenja. Rezultati su pokazali da je homogenost distribucije vitamina E i A na pločici povećana ukoliko se koristi bilo koji od nanokristala TiO2 u odnosu na homogenost samog uzorka i bilo koje kombinacije uzorak/matrica. Za ponovljivost rezultata u toku jednog dana pokazano je da se vrednosti varijacija sa određenim matricama smanju u odnosu na LDI. Međutim, sa supstratima je slika drugačija, vrednosti varijacija unutar jednog dana neuporedivo su niže nego što su vrednosti dobijene LDI i MALDI metodom. Isti trend kao za varijacije unutar jednog dana, zapaža se i za vrednosti varijacija između dana, ponovo su se supstrati pokazali kao znatno bolji izbor. Sumarno, pokazan je veliki potencijal koji imaju supstrati na bazi TiO2 za detekciju i kvantitativnu analizu vitamina E i A., In this work, we have compared mass spectra of vitamin E and A acquired with LDI TOF MS, MALDI TOF MS with organic matrices (DHB, 9-AA, CHCA and THAP) and SALDI TOF MS analysis with substrates based on TiO2 nanocrystals i.e. colloidal nanoparticles, prolate nanospheroids and nano tubes. Different size and shape of nanocrystals were used because of the already known fact that these factors have impact on desorption and ionization processes. The within-day and day-to-day precision LDI, SALDI and MALDI TOF MS was analysed using Excel tool (ANOVA). For calculation of homogeneity, we used the mean value of coefficient of variation of eight S/N values with nine repetition within three days for each analyte/substrate combination. The results showed that homogeneity of vitamin E and A was significantly improved when either of nanocrystals were used compared to LDI and MALDI approach. Within day precision with some matrices were slightly higher, but with some matrices precision were even lower comparing to LDI. The same pattern was observed with values of day-to-day variations, again nanocrystals were much better choice. In summary, it is shown that subrates based on TiO2 nanocrystals have the great potential for qualitative and quantitative analysis of vitamin E and A.

Surface-assisted laser desorption/ionisation time-of-flight mass spectrometry (SALDI-TOF-MS) might be the method of choice for the analysis of low mass molecules (less than m/z 500). Titanium dioxide (TiO2) nanocrystals as a substrate for SALDI-TOF-MS improve the reproducibility of the signal intensities and prevent the fragmentation of some molecules upon laser irradiation, as we have previously shown. In addition, variously shaped and sized TiO2 nanocrystals/substrates for SALDI-MS could be used for quantification of small molecules, which are otherwise difficult to detect with the assistance of organic matrices. TiO2-assisted LDI-MS spectra could be acquired with excellent reproducibility and repeatability and with low detection limit. In the current study, we analysed the spectra of dexasone, citric acid, vitamin E and vitamin A acquired with TiO2 nanocrystals of various shapes and dimensions, i.e. the colloidal TiO2 nanoparticles (TiO2 NPs), TiO2 prolate nanospheroids (TiO2 PNSs) and TiO2 nanotubes (TiO2 NTs). Various shapes and dimensions of substrates were used since these factors determine desorption and ionisation processes. The homogeneity on the target plate was compared based on signal-to-noise values of peaks of interest of analysed molecules as well as the within-day and day-to-day repeatability. In summary, the obtained results show that the applicability of individual TiO2 nanocrystals depends on the analyte. Signals which are acquired with the assistance of TiO2 PNSs have the highest sensitivity and reproducibility (the smallest standard deviation), even compared with those in the LDI mode. This implies that TiO2 PNSs could also be suitable for quantitative analyses of small molecules.

Ruthenium compounds are highly regarded as metallo-drug candidates. Many studies have focused their attention on the interaction between ruthenium complexes with their possible biological targets. The interaction of ruthenium complexes with transport proteins, enzymes and peptides is of great importance for understanding their biodistribution and mechanism of action, therefore, the development of an anti-cancer therapy involving ruthenium complexes has recently shifted from DNA targeting towards protein targeting. With the aim of gaining insight into possible interactions between ruthenium complexes with biologically relevant proteins, we have studied the interaction of cis-dichlorobis(2,2-bipyridyl-4,4-dicarboxylic acid)ruthenium(II) complex [Ru(II)(dcbpy)(2)Cl-2], which previously showed good potency in photo-dynamic chemotherapy, with bovine serum albumin (BSA), phospholipase A(2) (PLA(2)) and glutathione (GSH). Binding constants and possible number of binding sites to mentioned proteins and peptide are investigated by ultraviolet-visible spectroscopy and Matrix-Assisted Laser Desorption Ionization Mass Spectrometry (MALDI TOF MS). The complex binding affinities were in the following order: PLA(2) GT BSA GT GSH. Moreover, genotoxic profile of the complex, tested on peripheral blood lymphocytes as a model system, was also promising.

Titanium dioxide is widely used substrate for laser desorption and ionization [(SA)LDI] mass spectrometry. As the semiconductor with high UV absorbance and rapid energy transfer to analytes, TiO2 provides soft and efficient desorption/ionization of analytes with relatively low degrees of fragmentation in the gas phase. TiO2 nanocrystals are convenient for small molecules (molecular mass LT 1000 Da) analysis due to low number of background signals. Desorption/ionization processes on TiO2 nanocrystals are related to the physical properties of the substrate, such as the ability to absorb and dissipate energy from the irradiating laser light source. In addition, size and shape of nanocrystals also affect these abilities. The aim of this study is to investigate the influence of shape and size dependant TiO2 nanocrystals/UV laser interaction on the quality of the mass spectra, detectability of analyzed molecules, intensities of the signals and homogeneity of co-crystals onto the MALDI plate, of carbohydrates. It is shown that the size and shape of nanocrystals influenced the way of packing carbohydrates onto plate, and thus affects homogeneity and reproducibility of mass spectrometry analysis.

In the present study, the possibility for the application of TiO2 nanocrystals of various shapes and sizes, for substrate-assisted laser desorption and ionization time-of-flight mass spectrometric (SALDI TOF MS) quantitative analysis of small molecules (steroid hormones, amino acids and saccharides) was investigated. Parameters, such as homogeneity of the substrate/analyte distribution, reproducibility of the measurements, within-day, and day-to-day repeatability, were determined. The homogeneity of different nanocrystal/analyte combinations on the target plate were compared based on the signal-to-noise values of several analyte signals. Obtained results show that all TiO2 nanocrystals, regardless of their shape, have great potential for the detection and determination of steroid hormones, amino acids and saccharides with good analytical parameters and detection limits. On the other hand, the reproducibility of the S/N ratio and detectability of the analytes recorded in various modes differ depending on the substrate. All examined molecules were detectable in negative ion mode with TiO2 NTs, in contrast to all other organic matrices and substrates, and the best reproducibility was obtained with the larger nanocrystals, TiO2 PNSs and TiO2 NTs, making them good candidates for the quantitative determination of small molecules.

Phospholipids are the main components of biological membranes. This book covers the production, properties and use of natural and synthetic phospholipids as drug delivery systems for therapeutic agents, including small drugs, peptides/proteins and nucleic acids. Also covered in this book are major recent findings that elucidate the biochemical features of polyphenol-phospholipid interactions and their influence on the mechanical and biochemical properties of membranes; research on the metabolism of phospholipids and their fatty acids content, fragmentally altered in various diseases; information dealing with the various aspects of different metallodrugs with phospholipids and their analysis in the light of their importance in cancer therapy; the synthesis and metabolism of major membrane phospholipids; and an in-depth discussion on the synthesis of other phopholipids, including lecithin are examined as well.

Nanostructured materials as substrates for surface-assisted laser desorption and ionization time-of-flight mass spectrometry have two main advantages such as small number of signals in the low mass range and salt tolerance. We have also previously observed decreased extent of undesired fragmentation of bipyridine-containing transition metal complexes in the presence of TiO2 nanoparticles (NPs). In this work, we extended our previous study and tested whether both TiO2 NPs and TiO2 prolate nanospheroids (PNSs) can be used as substrates for SALDI-MS of bipyridine-containing transition metal complexes and whether they tolerate intense laser and the presence of inorganic salts. TiO2 NPs (an average diameter of 5 nm) and PNSs (length: 40-50 nm, the lateral dimension: 14-16 nm) were characterized microscopically and their mass spectra were analyzed, as well as the spectra of bipyridine-containing Pt(II) and Ru(III) complexes. Our results show that seven times higher analyte signals can be obtained in the presence of PNSs compared to the signals acquired with NPs and three times higher compared to spectra acquired without a substrate. The presence of inorganic salt did not affect the spectra, which makes both TiO2 nanocrystals suitable for MS analysis of transition metal complexes in biological fluids. (C) 2015 Elsevier B.V. All rights reserved.