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Four monitoring campaigns of sedimentable dust were provided from two large non-sanitary landfills (Zrenjanin and Novi Sad) in Serbia during 2021. Particle size analysis by laser diffraction and inductively coupled plasma-optical emission spectrometry were carried out in order to obtain the particle size distribution (PSD) and the toxic elements (TEs) concentrations. The health risk assessment of the landfill employees was performed according to the United States Environmental Protection Agency methods based on TEs concentrations. The PSD results demonstrated that the majority of sedimentable dust samples mass were not concentrated neither within PM2.5 neither within PM10 fraction. Analysis revealed high concentration of TEs at both landfills: an extremely high concentrations of Cr and Zn in samples from Zrenjanin landfill was detected. Health risk potential of elements was as follows for both landfills: Cr > Co > Pb > Ni > Zn > Cu. According to the results, maximal hazard index for landfill employees in Zrenjanin (0.197) and Novi Sad (0.113) showed that non-cancer risk was very low. For both landfill sites, cancer risk was highest for Cr (2.75×10-5 for Zrenjanin and 2.02×10-7 for Novi Sad), though still within the defined threshold for tolerable cancer risk., Na dve velike nesanitarne deponije u Srbiji (Zrenjanin i Novi Sad) sprovedene su četiri kampanje monitoringa taložne prašine. Analiza raspodele veličine čestica urađena je laserskom difrakcijom, dok je koncentracija toksičnih elemenata (TE) određena pomoću optičke emisione spektrometrije sa induktivno spregnutom plazmom. Procena rizika po zdravlje zaposlenih na deponijama sprovedena je na osnovu koncentracija TE prema metodama Agencije za zaštitu životne sredine Sjedinjenih Američkih Država. Rezultati raspodele veličine čestica su pokazali da najveći deo uzoraka taložne prašine ne pripada ni PM2,5 ni PM10 frakciji. Analiza je pokazala visoku koncentraciju TE na obe deponije: ustanovljena je izuzetno visoka koncentracija Cr i Zn u uzorcima sa zrenjaninske deponije. Potencijal analiziranih toksičnih elemenata u pogledu rizika po zdravlje za obe deponije je sledeći: Cr > Co > Pb > Ni > Zn > Cu. Prema rezultatima, ukupni (maksimalni) indeks opasnosti za zaposlene na deponijama u Zrenjaninu (0,197) i Novom Sadu (0,113) pokazao je da je rizik od kancera veoma nizak. Za obe deponije, rizik od kancera je bio najveći za Cr (2,75×10-5 za Zrenjanin i 2,02×10-7 za Novi Sad), čija je vrednost takođe u okviru definisanog praga tolerancije za rizik od kancera.

Antifungal agents are the group of drugs commonly prescribed in the treatment of fungal infections, which are widely spread among the global population. Their properties, such as absorption, distribution, metabolism, route of elimination or plasma protein binding (PPB), considerably influence their therapeutic success, while a number of the molecular physicochemical properties of the drug notably influence all these processes. Lipophilicity (log P), molecular weight (Mw), volume (Vol), polar surface area (PSA) and solubility (log S) play important roles in drug absorption, penetration into tis-sues, distribution and route of elimination or the degree of plasma protein bind-ing. In this study, the relationships between these five molecular properties of eight antifungal drugs and their plasma protein binding data obtained from relevant literature were investigated. The Selected physicochemical molecular descriptors of the drug were calculated using software packages. The estab-lished relationships between PPB and PSA; Mw; Vol and log S were showed relatively poor correlation (r < 0.35). The best correlation was obtained for the relationship between PPB data and the lipophilicity descriptor X log P3 (correlation coefficient r = 0.55). In further investigation, multiple linear reg-ression analysis was applied. The best correlation was obtained with applicat-ion of lipophilicity with polar surface area (r = 0.918) and volume (r = 0.916) or molecular weight (r = 0.896) as independent variables., Антифунгалнасредствапредстављајугрупулековакојисепримењујуулечењугљи-вичнихинфекција, данасширокораспрострањенихмеђуглобалномпопулацијом. Одњиховихособинакаоштосуапсорпција, дистрибуција, метаболизам, путелиминацијеиливезивањезапротеинеплазмe значајнозависињиховтерапеутскиуспех, абројнефизичко–хемијскеособинемолекулалекаутичунасвеовепроцесе. Липофилност(log P), молекулскамаса (Mw), запремина (Vol), поларнаповршина (PSA) ираствор-љивост (log S) играјуважнуулогууапсорпцијилека, продирањууткива, дистрибуцији, путуелиминацијеилистепенувезивањазапротеинеплазме. Уовомрадузаосаманти-фунгалнихлековаистраженисуодносиизмеђуособинамолекулаистепенањиховогвезивањазапротеинеплазме (PPB). Дескрипторифизичко–хемијскихособинамолекулаиспитиванихантифунгалнихлековаизрачунатисупомоћуодабранихсофтверскихпакета, доксуподациоњиховомPPBприкупљениизодговарајућелитературе. ОдносиизмеђуPPBиPSA, Mw, Volи log Sпоказалисулошукорелацију (r < 0,35) докјебољакорелацијадобијенајеизмеђуподатакаоPPBидеск рипторалипофилности, X log P3вредности (r = 0,55). Удаљемиспитивању, примењенајевишеструкалинеарнарегре-сионаанализа. НајбољезависностидобијенесуизмеђуPPBвредностиилипофилностиузприменуполарнеповршинемолекула (r = 0,918), волумена (r = 0,916) имолекулскемасе (r = 0,896) каонезависнопроменљивих.

This study represents a new strategy for discrimination of 59 samples of various cold-pressed, virgin and refined edible vegetable oils according to the corresponding botanical origin. Samples were produced from 17 plant species: olive, sunflower, safflower, flax, pumpkin, sesame, hemp, walnut, hazelnut, almond, grape, black cumin, apricot, plum, soybean, wheat and rapeseed. A GC/MS device performing in a ion current (IC) mode, combined with multivariate clustering, was employed in the analysis. Derivatization reaction occurred in the injector of a gas chromatograph. The discriminations between species were based on marker-peaks of 9 molecular ions of dominant fatty acid methyl esters (FAMEs), which were chosen as descriptors: m/z 268, 270, 292, 294, 296, 298, 324, 326 and 354. Dendrogram obtained after performing cluster analysis shows clear discriminations of the analyzed samples, based on the belonging botanical origin. These results demonstrate that IC-GC/MS approach with cluster analysis could be a useful tool in rapid screening for botanical origin of commercial samples of various edible vegetable oils.

The pK(a) values of twelve beta-hydroxy-beta-arylalkanoic acids and ibuprofen were determined using a modified RP-HPLC method. The stationary phase was octadecyl modified (C-18) silica gel, and the mobile phases were mixtures of methanol and one of ten different buffers (60: 40 volume ratio). The mean retention time of each compound was plotted against the pH of each of the ten used mobile phases. The inflection point of the obtained sigmoidal curve represents the (s)(w)pK(a) of a compound. Using (s)(w)pKa in previously established equations for the specific methanol/buffer mixture, the (w)(w)pK(a) values (in pure water) were calculated. The obtained wwpKa values for the synthesized compounds were in a range from 3.40 to 3.74, and the (w)(w)pK(a) for ibuprofen was 4.27. The Predicted pK(a) values for this type of compounds in the MarvinSketch 5.11.5. Program were in poor correlation with the experimental results, while in ACD//I-Labs pK(a) values were calculated as a wide range.

In this work, the behavior of the active pharmaceutical substances methylprednisolone (in a form of methylprednisolone sodium succinate) in finished pharmaceutical dosage form, i.e., freeze-dried powder for injections, was examined. The goal was to evaluate the chemical stabilities of methylprednisolone sodium succinate packaged in a dual chamber vial, as a specific container closure system. The effect of different parameters: temperature, moisture and light were monitored. The method proposed by United States Pharmacopeia was used to determine concentrations of methylprednisolone, as the sum of the concentration of methylprednisolone esters (17-hydrogen succinate and 21-hydrogen succinate) and free methylprednisolone. The HPLC method was used for stability evaluation of the active substance and determination of related substances. Four main degradation products were registered. Temperature has a major impact on the degradation process with the appearance of 3 degradation products (impurities B, C and D), while the presence of light caused an increasing content of impurity A. Identification of impurity B, C and D has been realized using mass and NMR spectroscopy. All three substances are substances related to methylprednisolone. © 2010 (CC) SCS., У овом раду испитиване су особине фармаколошки активне супстанце метилпреднизолона (у облику метилпреднизолон-натријум-сукцината) у готовом производу – лиофилизату за раствор за инјекције. Циљ рада је испитивање хемијске стабилности метилпреднизолон-натријум-сукцината у двокоморној бочици, као специфичном систему контактног паковања. Испитан је ефекат различитих параметара: температуре, влаге и светлости. За одређивање концентрације метилпреднизолона, као збирне концентрације метилпреднизолон естара (17-хидроген-сукцината и 21-хидроген-сукцината) и слободног метилпреднизолона, коришћена је метода описана у Америчкој фармакопеји. За испитивање сродних супстанци примењена је HPLC метода. Уочена су 4 деградациона производа. Доказано је да повећање температуре има највећи значај на процес деградације и утиче на повећање садржаја нечистоћа B, C и D, док присуство светлости доводи до повећања садржаја нечистоће А. Нечистоће B, C и D су идентификоване применом масене и NMR спектроскопије. Све три нечистоће су идентификоване као сродне супстанце метилпреднизолона.

In this work, the behavior of the active pharmaceutical substances methylprednisolone (in a form of methylprednisolone sodium succinate) in finished pharmaceutical dosage form, i.e., freeze-dried powder for injections, was examined. The goal was to evaluate the chemical stabilities of methylprednisolone sodium succinate packaged in a dual chamber vial, as a specific container closure system. The effect of different parameters: temperature, moisture and light were monitored. The method proposed by United States Pharmacopeia was used to determine concentrations of methylprednisolone, as the sum of the concentration of methylprednisolone esters (17-hydrogen succinate and 21-hydrogen succinate) and free methylprednisolone. The HPLC method was used for stability evaluation of the active substance and determination of related substances. Four main degradation products were registered. Temperature has a major impact on the degradation process with the appearance of 3 degradation products (impurities B, C and D), while the presence of light caused an increasing content of impurity A. Identification of impurity B, C and D has been realized using mass and NMR spectroscopy. All three substances are substances related to methylprednisolone., U ovom radu ispitivane su osobine farmakološki aktivne supstance metilprednizolona (u obliku metilprednizolon-natrijum-sukcinata) u gotovom proizvodu - liofilizatu za rastvor za injekcije. Cilj rada je ispitivanje hemijske stabilnosti metilpredni-zolon-natrijum-sukcinata u dvokomornoj bočici, kao specifičnom sistemu kontaktnog pakovanja. Ispitan je efekat različitih parametara: temperature, vlage i svetlosti. Za određivanje koncentracije metilprednizolona, kao zbirne koncentracije metilprednizolon estara (17-hidrogen-sukcinata i 21-hidrogen-sukcinata) i slobodnog metilprednizolona, korišćena je metoda opisana u Američkoj farmakopeji. Za ispitivanje srodnih supstanci primenjena je HPLC metoda. Uočena su 4 degradaciona proizvoda. Dokazano je da povećanje temperature ima najveći značaj na proces degradacije i utiče na povećanje sadržaja nečistoća B, C i D, dok prisustvo svetlosti dovodi do povećanja sadržaja nečistoće A. Nečistoće B, C i D su identifikovane primenom masene i NMR spektroskopije. Sve tri nečistoće su identifikovane kao srodne supstance metilprednizolona.

Asimple, rapid and accurate procedure for the quantitative determination of quercetin in its pure form and in formulations has been developed. The method is based on the spectrophotometric determination of a complex formed between quercetin and potassium titanyloxalate in 50 % ethanolic solutions. To characterize the quercetin titanyloxalato complex, the stability constants of the complex were determinated potentiometrically and spectrophotometrically at different temperatures (T = 26.0oC, 34oC and 39.0oC), as well as at different ionic strengths (I = 5.0x10-4 mol dm-3, 3.0x10-2 mol dm-3 and 6.0x10-2 mol dm-3) and the thermodynamic parameters were calculated. As quercetin is usually conjugated to vitamin C in pharmaceutical formulations, two procedures for the quantitative determination of quercetin by this complexing reaction were tested - both in the absence and presence of ascorbic acid. In both procedures, the Beer law was obeyed over the same concentration range of quercetin, i.e., 0.85 μg mL-1 - 16.9 μg mL-1. In the first procedure in the absence of ascorbic acid the molar absorptivity coefficient of the quercetin-titanyloxalate complex is a=2.49 x 104 mol-1 dm3 cm-1, Sandells sensitivity of the method is S = 1.35 x 10-2 μg cm-2 and the detection limit is d = 0.67 μg mL-1. Whereas, in the presence of ascorbic acid (second procedure) a = 3.04 x 104 mol-1 dm3 cm-1, S = 1.11 x 10-2 μg mL-1. The proposed method was verified for the determination of quercetin in pharmaceutical dosage forms., Predložen je brz, jednostavan i tačan metod za određivanje kvercetina u farmaceutskim sirovinama i doziranim oblicima.Metod je baziran na spektrofotometrijskom određivanju kompleksa formiranog između kvercetina i kalijum-titaniloksalata u 50 % etanolu. Određene su konstante stabilnosti kvercetin titaniloksalatnog kompleksa potenciometrijski i spektrofotometrijski na različitim temperaturama (T = 26.0oC, 34oC and 39.0oC) i jonskim jačinama (I = 5.0x10-4 mol dm-3, 3.0x10-2 mol dm-3 and 6.0x10-2 mol dm-3) i izračunati su termodinamički parametri. Kako se kvercetin uobičajeno nalazi zajedno sa vitaminom C u doziranim oblicima, predložene su dve procedure za određivanje kvercetina: bez i u prisustvu askorbinske kiseline.U obe predložene procedure, Beer-ov zakon važi u oblasti 00.85 μg mL-1 - 16.9 μg mL-1 kvercetina. Prema prvoj proceduri, molarni apsorpcioni koeficijent kvercetin–titaniloksalatnog kompleksa je a=2.49 x 104 mol-1 dm3 cm-1, Sandelova osetljivost metode je S = 1.35 x 10-2 μg cm-2, a limit detekcije je d = 0.67 μg mL-1. Prema drugoj proceduri, a = 3.04 x 104 mol-1 dm3 cm-1, S = 1.11 x 10-2 μg mL-1. Predloženi metod je primenjen za određivanje kvercetina u doziranim oblicima.