聚乙二醇接枝壳聚糖聚离子胶束的制备与体外表征研究

Diammonium glycyrrhizinate loaded methoxy PEG-grafted-chitosan polyion complex micelles: preparation and in vitro characterization

目的:制备载有甘草酸二铵(DG)的聚乙二醇接枝壳聚糖(mPEG-CS)聚离子胶束,考察胶束的理化性质及体外释放机制。方法:通过壳聚糖烷基化合成mPEG-CS,以三聚磷酸钠为引发剂,利用静电相互作用制备载有DG的mPEG-CS聚离子胶束。考察胶束的形态、粒径和zeta电位。用透析袋法研究载药胶束在不同介质中的释放动力学。结果:制得胶束的平均粒径为(38.2±0.9)nm;包封率为(97.6±0.7)%;胶束的稳定性良好;胶束的释放与释放介质的种类、pH值和浓度有关。结论:mPEG-CS是一种良好的制备聚离子胶束的高分子材料,聚离子胶束是离子型药物的良好载体。

Objectives： To prepare and characterize the diammonium glycyrrhizinate loaded methoxy poly（ ethylene glycol）-grafted-chitosan polyion complex micelles （mPEG-chitosan PIC micelles）. Methods： mPEG-chitosan was synthesized by alkylation of chitosan with mPEG-aldehyde, mPEG-chitosan PIC micelles were prepared using sodium tripolyphosphate as an initiator via the electrostatic interaction. The micelles were observed under the transmission electron microscopy（TEM）. Mean size and zeta potential values of the micelles were measured using a zetasizer based on the dynamic light scattering. In vitro release of the diammonium glycyrrhizinate-loaded mPEG-chitosan PIC micelles was measured using a dialysis method in various buffered solutions. Results： Diammonium glycyrrhizinate-loaded mPEG-chitosan PIC micelles were successfully prepared with an average diameter of （38.2 ± 0.9） nm. Encapsulation efficiency of diammonium glycyrrhizinate was（97.6 ± 0.7）%. The micelles were stable at room temperature for 1 month, and the release rate was dependent on the anionic patterns, pH values and concentrations of the release media.Conclusion：mPEG-chitosan PIC micelles could be used as a polymer carrier suitable for encapsulation of anionic drugs .