壳聚糖修饰的载穿心莲内酯介孔二氧化硅纳米粒的制备及其pH响应性释药性能考察

目的:制备壳聚糖修饰的载穿心莲内酯介孔二氧化硅纳米粒(CS/Ap-MSN),对其进行体外质量评价及p H响应性释药性能考察。方法:根据改良经典stober法一步合成了氨基修饰的介孔二氧化硅纳米粒(NH2-MSN),利用壳聚糖进行偶联修饰,表征其形貌及结构,通过体外释放试验考察CS/Ap-MSN在不同p H条件下的响应性释药性能。结果:CS/Ap-MSN的平均粒径(178.0±3.2)nm,多分散指数0.378±0.117,Zeta电位(34.04±0.22)mV,载药量和包封率分别为(27.8±1.7)%,(63.6±3.2)%,壳聚糖的修饰量6.3%。CS/Ap-MSN在p H 5.0的释放条件下,8 d累计释药量达53.3%;pH 7.4的释放条件下,8 d的累计释药量23.4%。结论:CS/Ap-MSN的体外释药具有p H响应性,累积释放量随p H减小而增大,且具有一定的缓释性能。

Preparation and pH Responsive Release of Andrographolide-loaded Mesoporous Silica Nanoparticles Modified by Chitosan

Objective: To prepare andrographolide-loaded mesoporous silica nanoparticles modified by chitosan(CS/Ap-MSN) and investigate its quality and pH-responsive release behavior. Method: Mesoporous silica nanoparticles modified by amino(NH₂-MSN) were synthesized by modified stober method in one step.Chitosan was covalently attached to exterior surface of NH₂-MSN,morphology and structure of this product were characterized.In viro drug release behavior of CS/Ap-MSN in different pH was investigated. Result: Mean particle size of CS/Ap-MSN was(178.0±3.2) nm,PDI was 0.378±0.117 and Zeta potential was(34.04±0.22) mV,drug loading efficiency and encapsulation efficiency were(27.8±1.7)% and(63.6±3.2)%,respectively;modification amount of chitosan was 6.3%.Cumulative release amount of CS/Ap-MSN reached to 53.3% at pH of 5.0 after 8 days;while cumulative release amount of CS/Ap-MSN reached to 23.4% at pH of 7.4 after 8 days. Conclusion: In vitro release behavior of CS/Ap-MSN shows pH-responsive characteristic and sustained-release characteristic,cumulative release amount increases with decreasing of pH.