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Information × Registration Number 0215U007198, 0113U003758 , R & D reports Title Directed modified mesoporous silica for the sustained release of biologically active compounds popup.stage_title Head Roik Nadiia Volodymyrivna, к.х.н. Registration Date 17-02-2015 Organization Institute of Surface Chemistry of the National Academy of Sciences of Ukraine popup.description2 The object of investigation – mesoporous organosilicas. The purpose of the work - to establish the influence of the functional coating of silica carrier on aromatic amino acid release from the intraporous space. Methods of research - IR spectroscopy, x-ray diffraction analysis, low-temperature adsorption-desorption of nitrogen, transmission electron spectroscopy, chemical analysis, UV spectroscopy. Mesoporous silica with hexagonally ordered pore channels was synthesized in water-ethanol-ammonia medium using cetyltrimethylammonium bromide as a template. Directed modification of outer surface of silica particles with 3-сhloropropyl and N- [N '- (N'-phenyl) -2-aminophenyl] -3-aminopropyl groups was carried out by post-synthetic activation in vapor and solvent phases, respectively. The structure of synthesized organosilicas was characterized using X-ray diffraction method, low-temperature nitrogen adsorption-desorption, transmission electron microscopy and chemical analysis of the surface layer. The ability of the mesoporous silica for controlled release of biologically active substances was studied on the example of para-aminobenzoic acid at pH = 6,86 and pH = 1,00 by use of UV spectroscopy. It was found that N- [N '- (N'-phenyl) -2-aminophenyl] -3-aminopropyl groups block entry into the pores of the carrier in a neutral environment, preventing the release of amino acid. At pH = 1,00 repulsion of positively charged surface amino groups located near by the entrances of the pores allows free release of para-aminobenzoic acid molecules from the pores of the carrier into the aqueous environment. Proposed approach can be used for synthesis of directionally modified silica materials with ordered mesoporous structure for controlled release of biologically active substances. Product Description popup.authors Дзязько Марина Олександрівна Трофимчук Ірина Миколаївна popup.nrat_date 2020-04-02 Close