【摘要】 背景:羟基磷灰石与高分子复合材料作为组织工程材料的报道很多,但多为粉体材料或块状材料,用于修复治疗时均存在一定的局限性。目的:制备纳米羟基磷灰石/壳聚糖-明胶复合缓释微球,观察其体外释药特性。设计、时间及地点:重复测量设计,于2008-01/10在北京工业大学材料科学与工程学院生物功能高分子实验室完成。材料:纳米羟基磷灰石、壳聚糖、明胶、庆大霉素。方法:利用微波辅助法,在pH=7的条件下,制备了针状羟基磷灰石。采用W/O型复乳化-交联技术制备纳米羟基磷灰石/壳聚糖-明胶载药复合微球。主要观察指标:①纳米羟基磷灰石/壳聚糖-明胶复合微球的表面形貌、粒径分布。②载药复合微球的载药量、包封率及药物累积释放率。结果:①纳米羟基磷灰石/壳聚糖-明胶载药复合微球形态均匀,其粒径主要集中在10～30μm,壳聚糖-明胶对羟基磷灰石形成了很好的包覆。②复合微球平均载药量32.97%,平均包封率49.20%,在3d内对庆大霉素的释放达到88%左右。结论:所制备的纳米羟基磷灰石/壳聚糖-明胶载药复合微球形态均匀,粒径分布窄,再分散性好,3d内能维持有效的药物浓度。更多还原

【Abstract】 BACKGROUND:Hydroxyapatite/polymer composite materials have been widely reported as tissue engineering materials;however,they are limited in repairing treatment because of the powder or piece in shape. OBJECTIVE:To prepare the nanohydroxyapatite(HAP) /chitosan-gelatin(CG) composite microspheres,and to observe the general drug release in vitro. DESIGN,TIME AND SETTING:Repeated measurement study was performed at Laboratory of Biological Functional Polymer,College of Material Science and Chemical Engineering,Beijing University of Technology between January and October 2008. MATERIALS:Nanohydroxyapatite,chitosan,gelatin,and gentamicin were used in this study. METHODS:Microwave irradiation method was used to synthesize aciform hydroxyapatite(pH=7) ,and W/O combined with multiple emulsification chemical crosslink technique was used to prepare nanohydroxyapatite/chitosan-gelatin composite microspheres. MAIN OUTCOME MEASURES:① Surface morphology and particle diameter distribution;② drug loading,entrapment efficiency,and cumulative release rate. RESULTS:① The composite microspheres were spherical in shape,and the particle diameter ranged from 10 to 30 μm. Hydroxyapatite was greatly embedded by chitosan-gelatin. ② The average drug loading was 32.97%,the average entrapment efficiency was 49.20%,and the cumulative release rate to gentamincin was near 88% within 3 days. CONCLUSION:The composite microspheres exhibit well-distributed morphology,narrow particle diameter distribution and good redispersibility. They can maintain an therapeutic concentration within 3 days.更多还原