、力学性能以及可靠的生物安全性,同时它又是良好的生长因子缓释载体[7] 。本实验采用物理方法制备PLGA膜,并根据需要表面吸附多种生长因子,电镜下观察到膜表面呈珊瑚状粗糙面,有利于骨细胞整合及稳定血凝块[8] ,而表面吸附的生长因子在骨形成早期能够及时释放。膜的另一侧呈光滑面,朝向软组织阻挡结缔组织长入。这种膜结构可使多种生长因子只向膜管内的骨缺损区一侧释放,既提高膜管内生长因子的浓度,又减少了外 源性生长因子的用量。
免疫组化结果表明,PLGA/bBMP+IGF-Ⅱ+bFGF组在2、4、8周时bBMP均显示阳性,而IGF-Ⅱ和bFGF在2周时显示弱阳性,但4周和8周时显示阴性,说明本实验制备的骨诱导再生膜在2周内对多种生长因子有良好的释放效应。8周时仍有bBMP表达,这可能与膜表面吸附其剂量较多有关,说明生长因子的缓释时间与其吸附量呈正相关。
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