pH梯度法制备氟嗪酸脂质体及质量评价

QUALITY EVALUATION OF OFLOXACIN LIPOSOMES PREPARATED BY A pH-GRADIENT METHOD

目的 :对用pH梯度法制备的氟嗪酸脂质体进行质量评价。方法 :用Sephadex 75葡聚糖凝胶柱分离 ,紫外分光光度法测定氟嗪酸脂质体包封率并进行体外渗漏测试。结果 :当大豆磷脂与胆固醇重量比为 4∶1,氟嗪酸与磷脂重量比分别为 1∶16、1∶8、1∶4时 ,包封率分别为 88.4%、86 .3%、74.1%。体外渗漏测试显示 ,在分别稀释 1、5、10倍后 1h测得渗漏率均小于 5 %。结论 :用pH梯度法制备的氟嗪酸脂质体包封率高 ,渗漏率低。

OBJECTIVE:To evaluate the quality of Ofloxacin liposomes preparated by pH gradient method.METHODS:Ofloxacin liposomes were prepared by pH gradient method and the encapsulation efficiency was determined by UV at 293 nm after the free drug molecules separated from Ofloxacin liposomes on a sephadex 75 minicolumn.RESULTS:The encapsulation efficiency was 88.4%, 86.3%, 74.1% respectively when the phospholipid/cholesterol weight ratio was 4∶1 and the drug/phospholipid weight ratios were 1∶16,1∶8,1∶4 respectively. The extent of leakage from liposome was examined after diluted with 0.9% NaCl at room temperature. The results showed that the extent ratios of leakage were lowered to 5% in an hour after diluted by 1, 5 and 10 times,respectively.CONCLUSION:A high encapsulation efficiency and low ratios of leakage Ofloxacin liposomes prepared by a pH Gradient Method was obtained.