海藻酸微球的制备及结构与性能间相互关系

采用高压静电液滴法制备海藻酸钙微球(AGS)。首先通过改进高压装置中电场环境,形成均匀电场,制备单分散AGS;在此基础上,以牛血清白蛋白、血红蛋白为药物模型,系统地研究载药微球的表面形貌、内部结构、溶胀比以及载药释药性能。实验结果表明:在电场中加入直径为17cm的圆形铁环,可有效减少子液滴的形成,制得粒径为(219±6)μm的单分散AGS;另外,海藻酸钠包载不同的药物将形成不同的AGS内部结构,进而影响AGS强度及载药释药性能。释放液中牛血清白蛋白的聚丙烯酰胺凝胶电泳显示,该制备方法并未对被包埋蛋白的相对分子质量产生影响,为AGS在蛋白类药物缓控释载体领域中的应用奠定了基础。

Preparation of alginate microspheres and the relationship between its structure and characterization

In this study, calcium alginate microspheres have been fabricated by a modified electrostatic droplet generation technique. The surface, internal structure, swelling ratio, encapsulation efficiency and release kinetic profiles of the microspheres were all investigated, using bovine serum albumin and hemoglobin as the model drugs. Experimental results showed that selection of a ring into the electrostatic droplet generation device enables the preparation of monodisperse alginate microspheres with a mean diameter of （219!6） /xm, when the ring is 17 cm in diameter. Moreover, due to the different interactions between alginate and drug, the alginate microspheres with different internal structures would be fabricated, which would further affect the drug loading and in vitro release properties. Finally, eIectrophoresis experiment illustrated that the process of encapsulation had no effect on the molecular weight of the entrapped protein. In conclusion, this study provides theoretical basis for the application of alginate microspheres as protein delivery systems.