以溶膠-凝膠法製備介孔CaO-B2O3-SiO2生醫玻璃

Abstract

In order to improve the biocompatibility between the implant and the bone tissue, a biologically active hydroxyapatite layer is formed at the implant-tissue interface. The deposition rate and performance of the hydroxyapatite layer was dependent on the structure of bioglass. Mesoporous bioglasses materials have received much interest because of their high specific surface area and pore volume, and exhibit better in vitro bone forming bioactivity compared to conventional bioglasses. In this study, mesoporous CaO-B2O3-SiO2 bioactive glass with high specific surface area was prepared by sol-gel process and the synthesis was accomplished by using nonionic surfactant (block copolymer) as the template, tetraethyl orthosilicate, calcium nitrate tetrahydrate and tributyl borate as the inorganic precursors. TGA, XRD, TEM and N2 adsorption-desorption isotherms were used to characterize the microstructure of the samples. TGA analysis showed that the calcination in air at temperature above 400℃ was needed to remove the surfactant completely from the mesopores. A broad band between 20 and 30o can be clearly noted in XRD pattern of mesoporous bioactive glass. It can be seen that after being calcined at 400～700℃ for 3 h the sample almost has an amorphous state, which is indicative of the internal disorder and glassy nature of this material. By the nitrogen absorption / desorption analysis found that the calcination temperature 600 oC, Ca/B ratio of 2:2, the use of triblock copolymer synthesis of mesoporous bioactive glass was informed that the average diameter of 62.48 A, specific surface area of 231.52 m2/g. The results reveales that a hydroxyapatite layer started to form on the surface in 4 hr after mesoporous CaO-B2O3-SiO2 mesoporous bioactive glass was immersing in simulated body fluid.