【摘要】 用冷冻干燥法制备不同比例的纳米羟基磷灰石/壳聚糖-明胶(n-HA/CS-Gel)三维多孔支架材料,加入含骨形态发生蛋白-2(BMP-2)基因的质粒后再次冷冻干燥,制成具有基因缓释功能的组织工程支架材料。对支架材料的形貌结构、力学性能、体外降解特性、质粒的体外释放特性及质粒完整性进行检测。结果显示:纳米羟基磷灰石均匀分散在支架材料中,随着其含量的增加,孔隙率减少,抗压强度提高,在体外降解速度减慢。质粒DNA在体外1～3d快速释放,并能够维持释放5周以上,随着纳米羟基磷灰石含量的增加,释放时间延长,释放出的质粒DNA能够保持完整性。具有基因缓释功能的n-HA/CS-Gel支架材料是一种有望用于临床的新型骨组织工程支架材料。更多还原

【Abstract】 Nano-hydroxyapatite/chitosan-gelatin network(n-HA/CS-Gel) scaffolds with different mass ratios of nano-hydroxyapatite were fabricated by freeze-drying. Plasmid DNA containing bone morphogenesis proteins-2 (BMP-2) was added into scaffolds and dried by freeze-drying. The morphology and structure,mechanical properties,in vitro degradation and DNA release kinetics of scaffolds were characterized. The results indicate that the addition of n-HA decreases slightly porosities of the scaffolds,while increases the compressive strength and steps down the degradation of the scaffolds in vitro. The scaffolds show rapid release of Plasmid DNA in 1-3 d and sustain release more than 5 weeks. The scaffolds has protective effects on the integrity of the plasmid DNA. The addition of n-HA steps down the release of plasmid DNA from scaffolds. The results suggest that the plasmid released n-HA/CS-Gel scaffold is a sort of hopeful candidate for bone tissue engineering.更多还原