Al^(3+)离子对卵磷脂聚集体结构的影响

Influence of Al^(3+) Ions on the Aggregation Structure of Egg-yolk Phosphatidylcholine

本文用浊度滴定(UV鄄Vis)、透射电镜(TEM)和激光光散射(QELS)等方法对Al3+离子与卵磷脂(EYPC)囊泡之间的相互作用及其这种相互作用对溶液中磷脂微结构的影响进行了研究。结果表明,一定量的Al3+离子使EYPC多层囊泡转变为线团状聚集体;Al3+与牛磺胆酸钠(TC)的协同作用可以破坏EYPC的多层囊泡结构,促进相转变,形成混合胶束。

It is known that phosphatidylcholine(PC)abstract:multi -lamellar vesicles can solubilize efficiently cholesterol in hu-man bile.Altho ugh the interaction of trivalent metal ions to PC bi-layer membrane has been wi dely studied,less attention has been given to effects of trivalent metal ions on PC vesicles,especially in the presence of bile salts.In this article,we examine d the interaction of egg-yolk phosphatidylcholine(EYPC)abstract:multi-lamellar vesicles with Al 3+ and sodium taurocholate TC/Al 3+ mixture in aqueous solution by using UV-Vis,FTIR,QELS and TEM tech-niques respectively.The results of TEM observation indicate that addition of Al 3+ changed EYPC multi-lamellar vesicles into random coils.The data of UV-Vis, FTIR,QELS and TEM showed that the mixture of TC and Al 3+ induced a phase transition from EYPC multi-lamellar vesicles to mixed micel les through the synergy of TC with Al 3+ .The phase transition occurred more easily when the molar ratio of TC and Al 3+ was less than1.But a less amount of Al 3+ and TC mixture could destroy EYPC multi-lamellar vesicles and decreased the solubility of EYPC in aqueous solution.It is suggested that the synergy of TC w ith Al 3+ will affect the capacity of PC multi-lamellar vesicles to solubilize choles terol in human bile.