海藻酸钠-壳聚糖微囊成型机理及其对大分子药物的载药、释药研究海藻酸钠-壳聚糖微囊成型机理及其对大分子药物的载药、释药研究

目的考察海藻酸钠-壳聚糖微囊成型机理及其对大分子药物的载药及释药特性。方法采用乳化胶凝法制备海藻酸钠-壳聚糖微囊,通过差示扫描量热法(DSC)探讨其成型机理。以牛血清白蛋白(BSA)为模型药,研究微囊对大分子药物的包载能力及释药特性。结果DSC分析结果显示,组成微囊的各材料间发生静电相互作用而成型。随药载比增加,微囊中BSA的载药量由9.20％增至35.08％;随壳聚糖浓度升高,载药量由30.29％升至38.12％。载药微囊中BSA在PBS(pH 7.4)与0.1 mol·L^-1 HCl中均呈两相释放;随CTS浓度增大,BSA在0.1 mol·L^-1 HCl中的释放减慢。结论制备的微囊圆整且分散性好,微囊对BSA具较高包载能力,并具一定的缓释作用。

Studies on the formation mechanism of alginate-chitosan microcapsule and its drug-loading and release properties on macromolecular drug

AIM: To investigate the formation mechanism, macromolecular drug loading capacity and release property of alginate-chitosan microcapsules (ACM). METHODS: ACM was prepared by emulsification-gelation method and its formation mechanism was studied by DSC analysis. Using bovine serum albumin (BSA) as model drug, the drug loading and release properties of the microcapsules on macromolecular drug were investigated. RESULTS: The results of DSC analysis showed that there is electrostatic interaction between materials encapsulated in the microcapsule. With the increase of BSA microcapsule ratio, the BSA loading percentage rose from 9.20% to 35.08%; and with the ascent of chitosan (CTS) concentration, the BSA loading percentage increased from 30.29% to 38.12%. The BSA microcapsules whowed a two-phase release in both 0.1 mol.L-1 HCl and phosphate buffer saline (pH 7.4). With the increase of CTS concentration, the BSA release more and more slowly in 0.1 mol.L-1 HCl. CONCLUSION: Spheric and well-dispersed alginate-chitosan microcapsules were prepared. The microcapsule showed good loading capacity to BSA as well as sustained release to a certain degree.