载普伐他汀钠的壳聚糖微球的制备及性能评价

Preparation and performance of pravastatin sodium-loaded chitosan microspheres

目的 制备一种包载普伐他汀钠，以获得长效释放的载药微球。方法 以京尼平为交联剂制备载普伐他汀钠的壳聚糖微球，考察壳聚糖相对分子质量、油相水相比、反应温度、搅拌速度等对壳聚糖微球形成的影响，通过扫描电镜观察其微观形貌，测定微球的包封率以及不同pH条件下的溶胀度，并考察了普伐他汀钠的体外累积释药情况。结果 载普伐他汀钠药微球体外释放时间长达31 d以上，反应条件不同，药物释放速度不同，普伐他汀的包封率可达54.7%。最佳制备条件为：壳聚糖的粘度为200~400 mPa.s，油水比10∶1，搅拌速度850 r/min，温度40 ℃。结论 京尼平交联载普伐他汀钠的壳聚糖微球具有较好的长效缓释能力，并且可通过调节交联时间控制其对药物的释放速度。

Objective To prepare pravastatin sodium- loaded chitosan microspheres to allow sustained drug release. Methods The drug- loaded chitosan microspheres were prepared by using genipin as the cross- linker. The influences of molecular weight of chitosan, volume ratio of oil and water, reaction temperature, and stirring speed on the formation of chitosan microspheres were investigated. The morphology of the microspheres was observed using scanning electron microscopy. The encapsulation efficiency, swelling ratio under different p H conditions, and in vitro drug release were measured. Results The in vitro release of pravastatin sodium could last for at least 31 days. The drug release rate varied with the reaction condition. The drug entrapment efficiency of the microsphere was 54.7%. The optimal processing conditions were as follows： chitosan viscosity of 200- 400 m Pa · s, oil- water proportion of 10∶1, stirring speed of 850 r/min, and reaction temperature at 40 ℃.Conclusion The pravastatin sodium- loaded microspheres show good sustained drug release property, and the drug release rate can be modified by controlling the cross-linking time.