Preparation and characterization of the sol-gel nano-bioactive glasses modified by the coupling agent gamma-aminopropyltriethoxysilane

The sol-gel derived bioactive glasses (SBG) have been used in bone-tissue engineering because of their excellent biocompatibility and osteoconductivity. In this study, nano-SBG was successfully achieved through a wet mechanical grinding technique, and to further improve its dispersibility and cells proliferation, a silane coupling agent was coupled onto the surface of nano-SBG. Gamma-aminopropyltriethoxysilane (APTES) was used to the surface modification of the nano-SBG (60 mol%SiO2, 36 mol%CaO, 4 mol%P2O5) by a wet-chemical method in a dynamic inert nitrogen atmosphere. The surface properties of the biomaterials before and after modification were characterized and compared using FTIR and XPS. The characteristic peaks in FTIR spectra indicated that -CH2CH3 and -NH2 groups appeared on the surface of modified nano-SBG, and also, XPS spectra analysis revealed that nitrogen element was detected and carbon concentration increased on the surface of nano-SBG after modification. The above analysis proved that the desired groups of APTES had been covalently bonded onto the surface of nano-SBG