LIPID MONOLAYER STATES AND THEIR RELATIONSHIPS TO BILAYERS
LIPID MONOLAYER STATES AND THEIR RELATIONSHIPS TO BILAYERS
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DOI：
10.1073/pnas.84.12.4089
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发表时间：
1987-06-01
影响因子：
11.1
通讯作者：
SIMON, SA
中科院分区：
文献类型：
--
作者：
MACDONALD, RC;SIMON, SA
不常见的方法形成和分析的脂质单分子层已经能够识别的几个单层状态和识别的分子组织密切对应的双层。通过将磷脂溶液[己烷/乙醇中的二肉豆蔻酰磷脂酰胆碱，9：1（体积/体积）]连续添加到恒定面积槽的空气/水界面来形成单层。该过程产生非常规的表面压力（π）。表面浓度（<$）等温线，其对于具有三个显著交点的直线的液晶单层而言，其中两个交点在常规π-π中不明显。等温线。π的线性变化的区域是可以解释的烷基链熵的面积依赖性。两个在较低的. pi处断开。限定两个链平行于表面的状态。第三个发生在塌陷时，这对应于未受应力的脂质体的真实平衡。双层膜的力学和热力学性质，特别是相变参数，与它们处于平衡状态的单层膜的力学和热力学性质密切对应。
Uncommon methods of formation and analysis of lipid monolayers have enabled the recognition of several monolayer states and the identification of that in which molecular organization corresponds closely to that of the bilayer. Monolayers were formed by continuously adding a solution of phospholipid [dimyristoyl phophatidylcholine in hexane/ethanol, 9:1 (vol/vol)] to the air/water interface of a constant-area trough. This procedure generates unconventional surface pressure (.pi.)-surface concentration (.GAMMA.) isotherms, which for liquid-crystalline monolayers of straight lines with three prominent intersections, two of which are not apparent in conventional .pi.-A isotherms. The regions of linear change of .pi. are explicable in terms of the area dependence of alkyl chain entropy. The two breaks at lower .pi. delimit states in whic both chains lie parallel to the surface. The third occurs at collapse, which corresponds to a true equilibrium for unstressed liposomes. Mechanical and thermodynamic properties of bilayers, particularly phase-transition parameters, correspond closely to those of monolayers with which they are in equilibrium.