N,N-双十二烷基壳聚糖/胆固醇混合单分子膜及自组装囊泡性质

Mixed N, N-dilauryl Chitosan/Cholesterol Monolayer and Corresponding Vesicle Property

研究了添加胆固醇对N,N-双十二烷基壳聚糖(N,N-dilaurylchitosan,DLCS)单分子膜以及自组装囊泡性质的影响.结果表明,引入少量胆固醇会导致DLCS膜的凝聚性下降;当胆固醇含量增加到一定程度后,混合膜的凝聚性增强.添加胆固醇可显著改变DLCS载药囊泡的药物释放行为,少量胆固醇可以提高载药囊泡的释放速率和平衡药物释放百分率;而较高含量胆固醇则可抑制囊泡的释放速率和降低平衡药物释放百分率.此外,囊泡平衡药物释放率与其单分子膜压缩模量呈现一定线性关系,这说明胆固醇的引入导致囊泡分子膜凝聚性的改变,从而改变囊泡的通透性.通过调节胆固醇的加入量,可以制得药物释放行为在一定范围内可控的自组装囊泡.

Influences of cholesterol on N,N-dilauryl chitosan （DLCS） monolayer and corresponding vesicle property were studied. Experimental results indicated that the properties of N, N-dilauryl chitosan monolayer and corresponding vesicle were evidently changed by introducing cholesterol in matrix. Mixed monolayers with lower fraction of cholesterol were less rigid and compressible than pure DLCS monolayer. As the content of cholesterol increasing, however, the rigidity and compressibility of mixed monolayer were increased. In parallel, both the rate of drug-release and the equilibrium drug-release ratio of the vesicles were increased with lower cholesterol content, and they could be decreased with increasing the cholesterol content. The equilibrium drug-release ratio of the vesicle was decreased with increasing the compressibility of corresponding material monolayer, showing a linear relationship. Experimental results provide a possible way for preparing DLCS vesicle with controlled drug-release behavior by adjusting content of cholesterol in vesicle matrix.