负载siRNA胶原/生物活性玻璃复合材料的合成

Synthesis of siRNA Loaded Collagen/bioactive Glass Composites

目的:制备负载siRNA胶原/生物玻璃复合材料,初步探讨胶原/生物活性玻璃复合材料同时作为诱导成骨的支架材料和siRNA缓释体系的可行性。方法:通过冷冻干燥法制备负载siRNA胶原/生物玻璃复合材料,检测支架材料表征、机械性能及降解速率。用SEM、共聚焦显微镜观察MC3T3-E1细胞在支架材料上的粘附和生长情况,通过q-PCR检测从支架释放的siRNA活性。结果:通过冷冻干燥法制备负载siRNA胶原/生物玻璃复合材料观察为海绵状材料,生物活性玻璃均匀分散在胶原材料中,抗压强度较低,孔隙率适宜。第1周时,支架降解率达30.7%。细胞在支架上形成伪足,紧密黏附材料表面,细胞之间连接紧密。从支架中释放siRNA noggin干扰效率16%(P<0.05),差异具有统计学意义。结论:通过冷冻干燥法制备的负载siRNA胶原/生物玻璃复合材料具有良好性能和生物相容性,随着支架降解siRNA从支架中释放,siRNA noggin保持一定活性。

Objective： To prepare siRNA loaded collagen/bioglass composites and to investigate the function of col- lagen/bioactive glass composites, inducing local osteogenesis as well as sustained resealing siRNA. Methods.. The loaded siRNA collagen/bioglass composites were prepared by freeze--drying method. The scaffold material charac- terization, mechanical properties, and degradation rate were evaluated. Micro CT was used to observe the adhesion and growth of MC3T3--E1 in scaffolds. The q--PCR was conducted to detect the activity of siRNA released from the composites. Results： The siRNA loaded collagen/bioglass composites was sponge--like material. Scanning elec- tron microscopy showed that the bioactive glass was evenly dispersed in the collagen material. Compressive strength was low and porosity was appropriate. After the first week, the degradation rate was 30.7%. Cells form pseudo- pods on the material, tightly adhered to the surface of the material. Compared to the control group, the expression of noggin in the experimental group decreased by 16% （P〈0.05）, the difference was statistically significant. Con- clusion： The siRNA loaded collagen/bioglass composite material prepared by freeze--drying composites has good performance and biocompatibility. As the scaffold degraded, siRNA released from the composites, and siRNA nog- gin remained partly active.