Krupska T. Structure and properties of nanocomposites fumed silica/levomycetine.

The thesis is devoted to investigations of basic physico-chemical regularities and determination of interfacial interactions parameters in systems containing levomycetine, water, cells and fumed silica. Inter molecular interactions in the system of levomycetine-water-silica was studied using a set of experimental methods (1H NMR, IR-, UV spectroscopies). Dependences of the interfacial water structure and its thermodynamic parameters were determined at different levomycetine concentration. The influence of cell-silica interfaces on the formation of bound water layers was studied in low-hydrated systems. The influence of created nanocomposites and surface content of levomycetine on probe of cellular systems was investigated. It was shown that optimum concentration of the antibiotic in the nanocomposite is in the range of 0.4-0.6 mmol/g at which the cellular system is inhibited much stronger then without silica. Microporous co-polymer of styrenedivinilbenzene was used as a model of intracellular space of partly dehydrated cells. The measurement of the structure of interfacial water and influence of some organic molecules (DMSO, CHCl3, CH4) on the water characteristics was studied using 1H NMR spectroscopy. The effect of structural and energetic heterogeneity of water in the pores of polymer was recognized for this model.