介孔-大孔生物活性玻璃的合成及其生物活性**◆

背景：多孔生物活性玻璃材料具有较大的比表面积、孔隙率以及贯通的孔道结构,可以加速羟基磷灰石沉积的动力学速率从而提高材料诱导形成新骨的能力。 目的：利用有机酸替代无机酸来合成新型介孔-大孔生物活性玻璃。 方法：将柠檬酸和P123加入到无水乙醇中,在室温下搅拌2 h至溶液澄清。依次加入正硅酸乙酯、四水硝酸钙和三磷酸乙酯,继续搅拌24 h。将所得溶胶倒入培养皿中,在室温下放置7 d,之后高温下烧结除去有机物模板。 结果与结论：①利用有机酸所制备的材料具有大孔结构,拥有较大的比表面积、孔隙率和孔径。②合成的介孔-大孔生物活性玻璃在人工模拟体液中可以诱导形成含碳羟基磷灰石,表现出了较好的生物活性,有望成为一种具有发展前景的骨缺损修复替代材料。

Synthesis and in vitro bioactivity of mesoporous-macroporous bioactive glass

BACKGROUND: As the bone substitute materials, the bioactive glasses with excellent bioactivity and biocompatibility are used to repair the bone defects. Especially, porous bioactive glasses are benefiicial to form bone in virtue of its high specific surface area and pore volume. OBJECTIVE: To utilize citric acid as a substitution of inorganic acid so as to synthesize self-assembled mesoporous- macroporous bioactive glass (MMBG). METHODS: Citric acid and P123 were dissolved in ethanol, and the mixture was continuously stirred for 2 hours. Tetraethyl orthosilicate, Ca(NO3)2•4H2O, and triethyl phosphate were then added to the solution and stirred for 24 hours, followed by putting the solution in a beaker for 7 days under static conditions. Finally, calcination was performed for removing the organic composition. Samples were evaluated by immersion studies in simulated body fluid. RESULTS AND CONCLUSION: The synthesized material had mesoporous-macroporous structure with high porosity and BET surface. The samples also showed good bone-forming activity. It is anticipated that the synthesized MMBG can be used in bone defect repairing and bone tissue engineering.