新型抗癌药依托泊苷脂质体的制备

 目的 制备依托泊苷脂质体，测定其含药量及包封率，对其体外释放及原料药的体外释放进行比较，并对脂质体灭菌后的稳定性进行考察。方法 采用薄膜-超声分散法制备依托泊苷脂质体，通过均匀设计优化处方，利用透析法测定其含药量及包封率，进行热压灭菌及⁶⁰Co灭菌两种灭菌方式，以粒径和包封率为指标考证灭菌后的稳定性。结果 按均匀设计的最优组合制备脂质体的含药量为（574.3±30.7）μg·mL^-1,平均包封率为（61.58±0.83）%，依托泊苷脂质体50 h累积释药（96.13±1.11）%,而其原料药3 h累积释药（97.10±1.84）%，热压灭菌的渗漏率比60Co灭菌的渗漏率高。结论 用薄膜-超声分散法制备的依托泊苷脂质体外观圆整，粒径小而均匀，体外释药达到了长效缓释的作用，⁶⁰Co灭菌后脂质体较稳定。

Preparation of a new antitumor drug etoposide-loaded liposomes

OBJECTIVE To prepare etoposide-loaded liposomes, determine its drug content and encapsulation efficiency, compare its in vitro release with that of etoposide power,and study its stability after sterilization METHODS The etoposide-loaded liposomes were prepared by film- ultrasonic wave dissolving techniques. The optimum formula was selected through uniform design. Dialytic method was used to determine drug content and encapsulation efficiency. Moist heat sterlization and⁶⁰ Co radiation sterilization were applied. The vesicle size and percolation rate were used as stability parameters RESULTS The drug content of etoposide-loaded liposomes prepared by the optimum formular was (574.3±30.7)μg·mL^-1. The average encapsulation efficiency was (61.58±0.83)%. The in vitro release of etoposide-loaded liposomes added up to (96.13±1.11)% in 50 h. The release of etoposide powder added up to (97.10±1.84)% in 3 h.The average percolation rate was higher with moist heat sterilization than with sterilization by⁶⁰ Co radiation CONCLUSION The etoposide-loaded liposomes prepared by film- ultrasonic wave dissolving techniques were regular in morphology, and their vesicle sizes were small and even. The liposomes were conformed to be sustained-release preparation through in vitro release experiments. They were stable after⁶⁰ Co radiation sterilization.