氧氟沙星PLGA微囊的制备、表征和影响包封率的因素

Ofloxacin-loaded PLGA Microcapsules:Preparation,Characterization and the Factors Affecting Loading Efficiency

氧氟沙星在眼科临床广泛应用,本研究以氧氟沙星作为模型药物,采用水/油/水(w/o/w)的复乳化和溶剂扩散技术制备氧氟沙星聚乳酸-聚乙醇酸(PLGA)微囊,对影响包封率的工艺参数如药物浓度、PLGA使用量、初乳复乳的搅拌速率进行研究,并对微囊的粒径、表面电位和表面形态的理化性能进行了表征。测试结果表明,根据优化工艺制备的氧氟沙星PLGA微囊的平均粒径511.9±14.6nm,zeta电位-17.97±0.80mV,包封率54.2%,载药量1.94%。包封率随PLGA使用量、初乳搅拌速率的增加而上升,随内水相药物体积和浓度的增加而下降。通过优化的水/油/水(w/o/w)复乳化和溶剂扩散技术制备氧氟沙星PLGA载药微囊的粒度分布窄,载药量和包封率适中,具有较好的临床应用前景。

PLGA microcapsules entrapping Ofloxacin as a model drug, which is widely used in Ophthalmic clinic, were prepared by a w/o/w double emulsification solvent diffusion method. The influence of formulation parameters such as the concentration and volume of the drug, amount of the polymer, stirring rate of primary and secondary emulsions were evaluated. The microcapsule size, zeta potential and morphological study were determined. The results show that the PLGA mierocapsules entrapping Ofloxacin based on the optimized parameters have the mean diameter 511.9±14.6nm, the mean zeta potential-17. 97 ±0. 80mV, the encapsulation efficiency 54. 2% and drug content 1. 94%. The encapsulation efficiency increased with the amounts of PLGA and the stirring rate of primary emulsion, while decreased with drug volumn and concentration. Prepared by an optimized w/o/w double emulsification solvent diffusion method, the Ofloxacin-loaded PLGA mierocapsules may have a better clinical application prospect in future for its narrow distribution, moderate drug content and encapsulation efficiency.