海藻酸盐/壳聚糖复合微球的制备及其控制释放作用

Preparation of Alginate/Chitosan Composite Microspheres and Their Application in Controlled Release

采用喷雾干燥法将活性成分包载到海藻酸钠微凝胶中,再经钙离子和壳聚糖交联得到复合微球。以维生素B2为模型药物探讨了微球的控制释放效果和机理。扫描电镜分析表明海藻酸钠微凝胶经复合交联后形成了团聚体结构。与单一钙离子交联的海藻酸盐微球相比,复合微球对维生素B2释放更慢,半数释放时间(t50)延长约6倍,且交联时间越长、交联剂用量越高,维生素B2释放越慢。当载药量介于16.0%～35.6%时,维生素B2释放时间达24h以上,释放过程主要受费克扩散控制。

The active ingredient was encapsulated in the alginate microgel using spray-drying technology. The microgel was crosslinked with calcium cations and ehitosan to prepare the composite mierospheres. Their application in controlled release was investigated using vitamin B2 as the model drug. SEM analysis indicated that the aggregate structure was formed after compositely crosslinking of alginate mierogel. In comparison with alginate microspheres crosslinked solely by calcium cations, the composite microspheres showed slower release of vitamin B2, with is0 prolonged by about 6 times. The longer the crosslinking time and higher dose of crosslinker, the slower the release of vitamin B2. The release time of vitamin B2 was extended to above 24 h at the loading amount of 16.0% - 35.6%. The release process was dominated by Fickian diffusion.