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In this doctoral dissertation, N-doped and N, S co-doped carbon cryogels were synthesized, and their application as adsorbents in the removal process of selected heavy metals (Zn, Cd, Hg) and pharmaceuticals (carbamazepine, naproxen, diazepam and diclofenac) from aqueous solutions was studied. The results of structural and surface analysis showed that incorporation of nitrogen/nitrogen-sulfur preserved the turbostratic structure of the carbon cryogel, but a significant increase of the specific surface area as well as change of surface chemistry for the doped/co-doped samples were observed. In order to investigate the adsorption performance and process optimization, a series of adsorption experiments were performed. The best adsorption performances were obtained for the doped/co-doped samples with the highest specific surface area values and pores dimension. The adsorption capacities of these samples regarding the removal of heavy metals and pharmaceuticals, obtained using the Langmuir isotherm, were higher compared to the pristine carbon cryogel. Desorption and regeneration experiments confirmed the satisfactory regeneration ability after the fourth adsorption- desorption cycle of selected heavy metals and pharmaceuticals. Test results for a river water samples with a standard addition of a heavy metals and pharmaceuticals mixtures showed a higher adsorption efficiency up to 20-30% for the selected doped/co-doped samples with the highest values of the specific surface area compared to the pristine carbon cryogel. It was also noticed that the presence of interferences of metal ions, cations and anions has no significant effect on the adsorption efficiency. The results presented in this doctoral dissertation show that by carbon cryogel doping/co-doping it is possible to obtain carbon materials which can be successfully used as adsorbents in wastewater treatment processes.

The biological activity of six structurally similar tetradentate Schiff base copper(II) complexes, namely [Cu(ethylenediamine-bis-acetylacetonate)] (CuAA) and five derivatives where two methyl groups are replaced by phenyl, (CuPP), CF3 (CuTT) or by mixed groups CH3/CF3 (CuAT), Ph/CF3 (CuPT), and Ph/CH3 (CuAP) has been investigated. The set of antioxidant assays was performed, and the results were expressed as IC50 and EC50 values. The series of complexes showed interesting bioactivity and were investigated for the determination of antioxidant, antifungal, antimicrobial, and cytotoxic activity. A significant antioxidant behavior was exhibited by complex CuAA, greater than Trolox in the Oxygen Radical Absorbance Capacity (ORAC) assay. Antibacterial assay over Gram-positive and Gram-negative pathogenic bacterial strains and some fungal pathogens were studied. Antiproliferative activity of complexes in two human tumor cell lines, breast adenocarcinoma MCF-7, colon adenocarcinoma LS-174, and normal fibroblast cells-MRC-5, examined the effect on cell cycle progression. The significant cytotoxic potential, comparable to cisplatin cytotoxicity, was determined in human breast cancer cell line-MCF-7 with IC50 values being 17.53–31.40μM and human colon cancer cell line-LS-174 with IC50 values being 15.22–23.92μM. All tested compounds showed nearly twice more selectivity toward cancer cell lines than normal cells. The interactions of complexes with human serum albumin (HSA), the most prominent protein in plasma, were investigated using spectroscopic fluorescence techniques. The complexes bind to human serum albumin at multiple sites (n=0.2–1.9), displaying a moderate binding constant Ka=4.1–12.4×104M−1. The molecular docking experiment effectively showed complex binding to HSA and DNA molecular fragments.

Molekulski obeleženi polimeri su funkcionalni materijali sa unapred definisanom selektivnošću ka određenom molekulu. Cilj ove disertacije bio je dobijanje i karakterizacija molekulski obeleženih polimera sa templatima iz klasa steroida (holesterol) i UV filtera (benzofenon-4). Sintetisano je nekoliko serija molekulski obeleženih polimera i njihovih neobeleženih analoga primenjujući nekovalentni pristup, tehnikom polimerizacije u masi. Dobijeni sorbenti su okarakterisani pomoću infracrvene spektroskopije, skenirajuće elektronske mikroskopije, fizisorpcijom azota, elementalnom analizom, kao i pomoću adsorpcionih izotermi. Na osnovu karakterizacije dobijenih polimera može se zaključiti da je proces obeležavanja za odabrane template uspešno izveden. Polimeri obeleženi holesterolom i benzofenonom-4 imaju veći kapacitet za vezivanje templata od neobeleženih analoga. Rezultati ispitivanja selektivnosti dobijenih polimera ukazuju da su dobijeni polimeri selektivni za vezivanje templata u odnosu na druga jedinjenja iz iste grupe. Ispitana je mogućnost primene dobijenih polimera za ekstrakciju benzofenona-4 iz vodenih rastvora. Pokušaji dobijanja molekulski obeleženih polimera za UV filtere na bazi ciklodekstrina, nisu, za sada, dali zadovoljavajuće rezultate. Molecularly imprinted polymers represent functional materials with predetermined selectivity towards chosen molecule. The goal of this dissertation was preparation and characterization of molecularly imprinted polymers with steroid templates (cholesterol) and UV filters (benzophenone4). Several series of imprinted polymers and their non-imprinted analogs were synthesized, applying non-covalent approach, by bulk polymerization. Prepared sorbents were characterized by infrared spectroscopy, scanning electron microscopy, nitrogen physisorption, elemental analysis and adsorption isotherms. Results show that imprinting process was successful. Polymers imprinted with cholesterol and benzophenone-4 as templates have higher binding capacities than corresponding nonimprinted analogs. Selectivity of imprinted polymers was tested, showing that imprinted polymers are selective towards template compared to similar compounds binding. The application of benzophenone-4 imprinted polymers for solid-phase extraction from aqueous solutions was examined. Preparation of imprinted polymers for UV filters based on cyclodextrins was not successful so far.