左氧氟沙星羧甲基壳聚糖缓释微球的制备及其体外释放研究

目的:探讨乳化交联法制备可植入左氧氟沙星羧甲基壳聚糖缓释微球的最佳工艺,了解微球体外释药规律.方法:按正交设计,考察不同壳聚糖浓度、投药比、交联度、乳化转速条件对质量指标的影响,选出最佳方案,进一步用转篮法检测微球的体外释放特性.结果:各因素对所制微球综合指标的影响大小依次为:壳聚糖浓度＞投药比＞乳化转速＞交联度,用优化后工艺制得微球平均粒径64.55μm,载药量21.69%,包封率58.07%,体外释放行为符合Higuchi方程,T 50为47.01 h,7 d累计释放量72.02%.结论:本法所制缓释微球工艺稳定,微球在体外具有缓释作用.

Preparation and in vitro release of levofloxacin carboxymethyl chitosan sustained-releasing microsphere

Objective: To study the optimum technique for preparing implantable levofloxacin carboxymethyl chitosan (LVFX/CMC) sustained-releasing microsphere with emulsification and cross-linking process and to investigate the product release characteristic in vitro. Methods: Orthogonal test based on 4 factors: CMC concentration,CMC/LVFX (M/M),CMC/ glutaraldehyde (M/M) ,stirring speed, was employed to determine the optimum preparing technique of microsphere. The in vitro release characteristic of the microsphere was observed with basket rotating method. Results: The order of the importance of the 4 factors on quality of microspheres was CMC concentration > CMC/LVFX (M/M )> stirring speed >CMC/ glutaraldehyde (M/M). Microsphere prepared with the optimized method had a mean diameter of 64. 55 jum,a drug content of 21. 69%, and an enveloping rate of 58. 07%. The in vitro release accorded with Higuchi equation. T50 was 47. 01 h and 72. 02% of the drug was released in 7 A. Conclusion: Our preparing technique for LVFX/CMC microsphere is successful,and the release of LVFX from the microsphere is sustained in vitro.