Mu Xiaomei, Zhong Zhensheng
Department of Chemistry & Chemical Engineering, Zhongkai University of Agriculture and Technology, Guangzhou 510225, PR China.
Int J Pharm. 2006 Aug 2;318(1-2):55-61. doi: 10.1016/j.ijpharm.2006.03.016. Epub 2006 Mar 22.
The purpose of this work is to evaluate the improvement in physical stability of poly(vinyl alcohol) (PVA) modified liposomes. Liposomes composed of soya phosphatidylcholile (SPC) and cholesterol (1:1 molar ratio) were prepared by reverse phase evaporation method. Two types of interaction between liposome and PVA were investigated: PVA addition into lipid bilayer during liposome preparation and coating of already formed liposomes with PVA. The microparticles system was morphologically characterized by transmission electron microscopy (TEM) and particles analysis. Changes in particles size and zeta potential confirmed the existence of a thick polymer layer on the surface of liposomes. The amount of PVA adsorbing to liposomes and the encapsulation efficiency increased with increasing polymer concentration. The physical stability was evaluated by measuring the release rate of contents at 20 and 37 degrees C, the PVA modified liposomes were more stable than the conventional liposomes. Comparing with PVA-coated liposomes, the liposomes with PVA addition to the bilayer were more stable, and had higher entrapment efficiency.
这项工作的目的是评估聚（乙烯醇）（PVA）修饰脂质体的物理稳定性的改善情况。通过反相蒸发法制备了由大豆磷脂酰胆碱（SPC）和胆固醇（摩尔比1:1）组成的脂质体。研究了脂质体与PVA之间的两种相互作用类型：在脂质体制备过程中将PVA添加到脂质双层中以及用PVA包被已形成的脂质体。通过透射电子显微镜（TEM）和颗粒分析对微粒系统进行了形态学表征。粒径和zeta电位的变化证实了脂质体表面存在一层厚厚的聚合物层。吸附到脂质体上的PVA量和包封效率随聚合物浓度的增加而增加。通过测量20℃和37℃下内容物的释放速率来评估物理稳定性，PVA修饰的脂质体比传统脂质体更稳定。与PVA包被的脂质体相比，向双层中添加PVA的脂质体更稳定，并且具有更高的包封效率。
