盐酸环丙沙星/二氧化硅复合粒子的原位制备及其缓释性能

In situ preparation of ciprofloxacin hydrochloride/silica composites and their sustained release properties

利用硅酸钠在盐酸环丙沙星的酸溶液中的原位水解成功制备了盐酸环丙沙星/二氧化硅复合粒子.对所得产品进行的SEM、TEM、粒度分布、XRD和FTIR等分析表明,盐酸环丙沙星/二氧化硅复合粒子为粒径0.3～0.7μm的球形粒子,呈无定形态,且盐酸环丙沙星与二氧化硅以物理方式结合.热重分析结果表明,所得复合粒子药物负载量约为28.8%（质量分数）.体外溶出实验证明,产品具有良好的缓释性能,药物释放主要受扩散控制,具有均匀的释放速率和持久的缓释时间.

Ciprofloxacin hydrochloride/silica composites have been prepared by in situ hydrolysis of sodium silicate in an acidic ciprofloxacin hydrochloride solution. Characterization by SEM, TEM, particle size distribution, XRD and FTIR indicated that the amorphous composite particles had a spherical morphology with a diameter of 0.3- 0.7μm, and that ciprofloxacin hydrochloride was combined with silica via a physical process. Thermogravimetric analysis showed that the amount of ciprofloxacin hydrochloride entrapped in the composites was about 28. 8% （mass fraction）. In vitro release studies demonstrated that the composites had excellent sustained release properties with a constant release rate and a long release period and furthermore, that the release of the drug was mainly controlled by diffusion.