Thermodynamics of phosphatidylcholine-cholesterol mixed model membranes in the liquid crystalline state studied by the orientational order parameter.
Thermodynamics of phosphatidylcholine-cholesterol mixed model membranes in the liquid crystalline state studied by the orientational order parameter.
复制标题
通过取向有序参数研究液晶态磷脂酰胆碱-胆固醇混合模型膜的热力学。
DOI：
10.1016/s0006-3495(89)82757-2
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发表时间：
1989
影响因子：
3.4
通讯作者：
J. Freed
中科院分区：
文献类型：
--
作者：
Y. Shin;J. Freed
It is shown that good estimates of the activity of cholesterol in phosphatidylcholine-cholesterol mixed model membranes are obtained by examining the orientational order parameter S of cholestane spin probe (CSL) that is obtained from electron spin resonance by spectral simulation. By introducing thermodynamic stability conditions of liquid mixtures, the variation of activity (or S) as a function of cholesterol mole fraction is utilized to predict the concentration at which the phase separation occurs. These results for DMPC and cholesterol binary mixtures agree very well with those of Tempo-partitioning experiments. The comparison of activity coefficients and the phase boundary in DMPC/cholesterol mixtures with those of POPC/cholesterol mixtures suggests that acyl chain unsaturation leads to poorer mixing of cholesterol in phosphatidylcholine model membranes at higher temperatures (i.e., greater than 35 degrees C). In ternary solutions of DMPC, POPC, and cholesterol, it is found that cholesterol shows less deviation from ideality than in either of the two binary mixtures, and this implies that the phase separation occurs at higher cholesterol concentration than in either of the two binary mixtures. The present analysis suggests that there may not be a critical point in DMPC/cholesterol mixtures, even though phase separation does occur.
影响因子：
2.9
作者：
Presti,FT;Chan,SI
通讯作者：
Chan,SI
通过电子自旋共振进行横向扩散的动态成像以及模型膜中旋转动力学的研究。
影响因子：
3.4
作者：
Shin,YK;Freed,JH
通讯作者：
Freed,JH