不同表面活性剂对伊文思蓝脂质体体内外性质的影响

The effect of surfactants on properties of Evens blue liposome in rats

目的 寻找与二硬脂酰磷脂酰乙醇胺 聚乙二醇 (DSPE PEG)功能相似的表面活性剂 ,以增加脂质体的稳定性 ,改善其体内分布 ,提高靶向性。方法 制备伊文思蓝 (EB)脂质体 ,考察胆固醇与磷脂的比例对伊文思蓝脂质体包封率的影响 ;比较用DSPE PEG、吐温 80 (Tween 80 )和苄泽 3 5 (Brij 3 5 )修饰后的EB脂质体的包封率和在大鼠体内组织分布状况的变化。结果 EB脂质体的包封率最高为 2 5 3 0 %。用DSPE PEG、Tween 80和Brij 3 5修饰后使EB脂质体的包封率略有下降 ,但差别不显著 ;体内分布实验结果显示 :修饰后的脂质体在肝、脾和肾中EB的浓度均有不同程度的降低 ,脑中EB的浓度有所提高 ,而且以Tween 80修饰组最显著。结论 DSPE PEG、Tween 80和Brij 3 5对EB脂质体的包封率影响较小。Brij 3 5对EB脂质体的作用与DSPE PEG相似 ,能提高脂质体逃避网状内皮系统吞噬的能力 ;Tween 80主要能增加EB脂质体在大鼠脑组织中的分布 。

Objective To improve the stability,optimize the tissue distribution of Evens blue (EB) liposome,some surfactants such as DSPE PEG,Tween 80 and Brij 35 were used to modify the Evens blue liposome.Methods The Evens blue liposome was prepared by the reverse phase evaporation method.The effect of cholesterol on the encapsulation percentage of Evens blue was studied.The effects of DSPE PEG,Tween 80 and Brij 35 on the encapsulation percentage and tissue distribution of Evens blue liposome in the rat were determined.Results The top encapsulation percentage of Evens blue liposome is 25 30%.After modification by DSPE PEG,Tween 80 and Brij 35,the encapsulation percentages decreased a little,but not significantly.After modification,the Evens blue concentrations in the liver,spleen,lung and kidney were decreased,but the Evens blue concentration in the brain was increased,especially in the EB L Tween 80 group.Conclusion DSPE PEG,Tween 80 and Brij 35 had a little effect on the encapsulation percentage of Evens blue liposome.The effect of Brij 35 on the distribution of Evens blue liposome was similar to that of DSPE PEG because they both could prevent the clearance of reticuroendothelial systems (RES) to liposome.The Evens blue concentration in the brain greatly increase if the EB liposome is modified by Tween 80 in advance;this offeres a good information for preparing liposome targeting on the brain.