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A chemical characterization and biological activity of 7 honey types (multifloral, linden, rapeseed, sunflower,phacelia, acacia and honeydew honey) from different regions of Serbia were presented. The physicochemicalcharacteristics, mineral content, antioxidant and antimicrobial activity were estimated and discussed. All honeysshowed good nutritional characteristics, according to the adopted criteria of the standard codex for honey. Theconcentrations of 15 elements in honey samples were determined using inductively coupled plasma opticalemission spectroscopy (ICP-OES). Limits of quantification were in the range from 0.003 mg/kg (Cd, Cr, Cu, Mn,and Pb) to 1.50 mg/kg for sodium. Precision was expressed as relative standard deviation and its values werelower than 1.50%. Accuracy was evaluated with certified reference material (fish protein, DORM 4, NRC andcooking chocolate, SRM 2384, NIST) and obtained recovery percentages were 71-127%. The content of the mostabundant elements (K, Mg, and Na) and microelements (Al, Cu, Fe, Mn, Ni, Se, Si, and Zn) showed a significantvariability in accordance of their botanical and geographical origin, but also the influence of harvest conditions.The levels of toxic metals (As, Cd, Cr, and Pb) are much lower than the maximal allowed for these metalsaccording to European Commission Regulation. The antioxidant activity was evaluated by DPPH(Diphenylpicrylhydrazyl) assay while antimicrobial activity against Gram positive and Gram negative bacteria(E. coli and S. aureus) and fungi Candidi albicans was estimated by microdilution assay. The free radicalscavenging assay (%RSA) varies significantly among the honey samples. The highest antioxidant activity wasobserved with honeydew honeys (over 75% RSA) and the lowest was observed in the acacia, ranging from 22.96to 24.57% RSA. All honeys tested in this study exhibited antibacterial activity, with inhibition of bacterialgrowth, generally the higher against E. coli (80% for linden honeys) than against S. aureus (mostly much lowerthan 50%). Activity against Candidi albicans was almost negligible. The dataset composed of all experimentalresults was subjected to a chemometric evaluation and cluster analysis as hierarchical nonsupervised methodwas applied. According to the obtained outcome of applied algorithms, both botanical and geographical originhave important role in the elemental composition, antioxidant and antimicrobial activities. This is the peer-reviewed version of the following article: Đogo Mračević, S.; Krstić, M.; Lolić, A.; Ražić, S. Comparative Study of the Cheical Composition and Biological Potential of Honey from Different Regions of Serbia. Microchemical Journal 2020, 152, 104420. [https://doi.org/10.1016/j.microc.2019.104420]. Supplementary material: [https://cherry.chem.bg.ac.rs/handle/123456789/4996]

Binary polymeric amorphous carvedilol solid dispersions were prepared using solvent method by varying solvent type, polymer type and carvedilol to polymer ratio in order to assess the influence of these factors and maximize carvedilol dissolution rate. Low and high molecular weight polyvinylpyrrolidone, polyvinylpyrrolidone-vinyl acetate copolymer and polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer were used as polymeric carriers in carvedilol to polymer ratios 1:1, 1:2 or 1:4, while absolute ethanol or acetone were used as solvents. Hard gelatin capsules were prepared with carvedilol solid dispersion and lactose monohydrate, mannitol or microcrystalline cellulose. FTIR and PXRD were used to detect carvedilol crystallinity and identify carvedilol-polymer interactions and carvedilol polymorphs. These techniques confirmed carvedilol transition to amorphous state and suggested that hydrogen bonds were formed between carvedilol and polymer molecules. Carvedilol dissolution rate was significantly higher from solid dispersions with higher carvedilol to polymer ratio and solid dispersions prepared using the solvent in which the polymer was more soluble. Solid dispersion with polyvinylpyrrolidone-vinyl acetate copolymer in 1:4 ratio in absolute ethanol displayed the highest carvedilol dissolution rate with 91.78% carvedilol dissolved in the first 30 min. Capsules prepared with the selected solid dispersion and microcrystalline cellulose as diluent displayed the highest carvedilol dissolution rate, with 93.43% carvedilol dissolved within the first 30 min. Carvedilol bioavailability was significantly increased by formulating solid dispersions, while the analysis of serum biochemical parameters excluded damage on liver and kidney function and the lipid profile of animals exposed to investigated drug delivery system.