Phase equilibria in binary mixtures of phosphatidylcholine and cholesterol.
Phase equilibria in binary mixtures of phosphatidylcholine and cholesterol.
复制标题
磷脂酰胆碱和胆固醇的二元混合物中的相平衡。
DOI：
10.1021/bi00518a042
复制
发表时间：
1981
期刊：
影响因子：
2.9
通讯作者：
H. Mcconnell
中科院分区：
文献类型：
--
作者：
D. Recktenwald;H. Mcconnell
两种自旋标记物，即2,2,6,6 - 四甲基哌啶基 - 1 - 氧基和一种头部基团自旋标记的磷脂酰乙醇胺（L -α - 二棕榈酰磷脂酰 - N - 乙醇胺）的顺磁共振光谱已被用于研究二肉豆蔻酰磷脂酰胆碱和胆固醇二元混合物中的固 - 液和液 - 液分相。对这些共振光谱的定量分析支持这样一种观点：在低于磷脂的链熔化温度θm的温度下，且当胆固醇摩尔分数Xc小于0.2时，这些混合物由两相组成，一相是基本纯净的二肉豆蔻酰磷脂酰胆碱的固相，另一相是胆固醇摩尔分数等于0.2的液相。自旋标记数据还为在高于二肉豆蔻酰磷脂酰胆碱的链熔化转变温度时双层膜中的液 - 液不混溶性提供了证据。
The paramagnetic resonance spectra of two spin-labels, 2,2,6,6-tetramethylpiperadinyl-1-oxy and a head-group spin-labeled phosphatidylethanolamine (L-alpha-dipalmitoylphosphatidyl-N-ethanolamine), have been used to study solid-liquid and liquid-liquid phase separations in binary mixtures of dimyristoylphosphatidylcholine and cholesterol. A quantitative analysis of these resonance spectra supports the view that at temperatures below theta m, the chain-melting temperature of the phospholipid, and at cholesterol mole fractions Xc less than 0.2, these mixtures consist of two phases, a solid phase of essentially pure dimyristoylphosphatidylcholine and a fluid phase having a mole fraction of cholesterol equal to 0.2. The spin-label data also provide evidence for fluid-fluid immiscibility in the bilayer membrane at temperatures above the chain melting transition temperature of dimyristoylphosphatidylcholine.