resumo
Recently the sol-gel synthesis of biomaterials has been extensively studied owing to the significant advantages of this method. The room temperature synthesis, the metal-organic precursors and organic solvents, as well as the possibility of controlling the chemical conditions of the sol-gel process allow the introduction of organic and bioorganic molecules within the inorganic network. In the present study, results on sol-gel synthesis and structure of hybrid materials containing silica and chitosan are described and discussed. Four different types of silicon precursors were used: TEOS, TMOS, MTES and ETMS. The hybrids were prepared by replacing different quantity of the inorganic precursor with the organic component chitosan. The structure of the obtained hybrid materials was studied by FT-IR spectroscopy, XRD, NMR, AFM, BET and SEM. FT-IR spectra of the synthesised materials on the basis of ETMS and MTES indicated strong chemical bonds such as Si-C, Si-OC2H5 and Si-OCH, between the organic and inorganic components of the hybrids. AFM studies showed the presence of structural features with nanometer dimension. Whole cells of thermophilic Bacillus sp. UG-5B strain with 4-cyanopyridine degrading activity were successfully immobilised on the obtained biomaterials.
palavras-chave
SOL-GEL; SILOXANE HYBRIDS; POLYMER; TEMPERATURE; CATALYSIS; COATINGS; SUPPORT; CELLS; UREA
categoria
Chemistry; Materials Science
autores
Chernev, G; Samuneva, B; Djambaski, P; Kabaivanova, L; Emanuilova, E; Salvado, IMM; Fernandes, MHV; Wu, A