生物活性聚乳酸/SiO2-CaO复合薄膜的制备和表征

摘要

以聚乳酸、正硅酸乙酯和硝酸钙为原料,采用溶胶-凝胶方法制备了不同比例的聚乳酸/SiO2-CaO多孔复合薄膜.采用扫描电子显微镜和红外光谱仪对薄膜的微观结构和组成进行分析,并利用表面Zeta电位测定仪对其表面电位进行表征,通过模拟体液浸泡实验和MTT方法对薄膜的生物活性和细胞毒性进行评价.结果表明:复合薄膜在模拟体液中经过7d的浸泡,薄膜表面形成了环状结构的类骨磷灰石层;随着SiO2-CaO含量增加,复合薄膜表面微孔的孔径变小,薄膜表面Zeta电位变负,诱导类骨磷灰石沉积的能力增强;MTT实验证实复合薄膜对MG-63细胞没有毒性且有利于细胞的增殖.%A novel porous poly (lactic acid) (PLA)/SiO2-CaO(n(SiO2)∶n(CaO)=1:1) composite membrane is synthesized by Sol-Gel method.The microstructure and composition of the composite membranes are characterized by Fourier transform infrared (FTIR) spectroscope and scanning electron microscope (SEM).The surface zeta potential is monitored by the SurPASS electrokinetic analyzer.The bioactivity is evaluated by investigating the formation of apatite on the surface of the composite membranes in simulated body fluids and the cytotoxicity is evaluated by MTT experiments.After soaked in simulated body fluids for 7d,the surface of the PLA/SiO2-CaO composite membranes is covered by an apatite layer with an orderly ring structure.The surface zeta potential of the composite membranes decreases with increasing SiO2-CaO contents suggesting better bioactivity.The PLA/SiO2-CaO composite membranes do not induce cytotoxcity to MG-63 cells and support cell proliferation.