糖类交联明胶微球的制备及其释药特性研究

目的:以生物相容性的糖作交联剂制备明胶药物载体并研究其释药特性。方法:用葡萄糖、葡聚糖、氧化葡萄糖、氧化葡聚糖作交联剂制备明胶盘和微球,测定其溶胀动力学,分别以阿司匹林和牛血清白蛋白为药物模型,紫外分光光度法测定药物包裹率、载药率,并检测明胶微球在模拟体内条件下药物的释放速率。结果:葡萄糖、氧化葡萄糖、葡聚糖、氧化葡聚糖作交联剂制备的凝胶溶胀率分别为204%、246%、166%、233%;4种阿司匹林和牛血清白蛋白明胶微球平均载药率分别为8.73%和4.05%,平均包封率分别为62.55%和31.40%;2h药物释放百分率依次为30%、14%、76%、73%和97.2%、86.6%、60.8%、50.1%。结论:上述4种糖均可以取代化学交联剂制备明胶微球;天然糖交联微球缓释效果优于氧化糖。

Preparation and Release Characteristics of Gelatin Microspheres Cross-linked by Sugar

OBJECTIVE:To prepare gelatin drug carrier with biocompatible sugars as crosslinking agents and study its drug release characteristics.METHODS:Gelatin discs and microspheres cross-linked by glucose,dextran,oxidized glucose,and oxidized dextran were prepared and their swelling kinetics were determined as well.The encapsulation efficiency and drug loading rate were determined by UV spectrophotometry with aspirin and bovine serum albumin(BSA)as drug models respectively.The release rates of gelatin microspheres in simulated body were determined.RESULTS:The swelling degrees of gelatins cross-linked by glucose,oxidized glucose,dextran,and oxidized dextran were 204%,246%,166%,and 233%,respectively.The average drug-loading rate of aspirin gelatins was 8.73% as compared with 4.05% of BSA gelatin microspheres,with the average encapsulation rate of 62.55% vs.31.40%.The accumulate release rates in 2 h were 30%,14%,76%and 73% for aspirin gelatin microspheres as compared with 97.2%,86.6%,60.8% and 50.1% for BSA.CONCLUSION:All of 4 kinds of sugars can replace chemical crosslinkers for the preparation of gelatin microspheres.The natural sugar gelatin microspheres were superior to oxidized sugar in sustained release effect.