Stauffer Laboratory of Physical Chemistry, Department of Chemistry, Stanford University, Stanford, CA 94305.
Proc Natl Acad Sci U S A. 1989 Sep;86(17):6445-8. doi: 10.1073/pnas.86.17.6445.
Fluorescence microscopy can be used to visualize coexisting fluid phases in lipid monolayers composed of cholesterol and dipalmitoyl phosphatidylcholine under specified conditions of temperature, composition, and lateral pressure. At a critical composition of approximately 30 mol% cholesterol, decreasing the average molecular area below a(c) [unk]50 A(2) per molecule forces the binary mixture through a critical point, where the monolayer becomes homogeneous. At molecular areas approximately 10% above this critical area, we observe shape transitions from liquid domains with circular shapes to domains with less symmetrical shapes. Shape transitions and critical shape fluctuations can also be triggered with light, due to photochemical effects on the monolayer. Shape fluctuations of lipid domains can thus be used to sense chemical events at the air-water interface.
荧光显微镜可用于在特定温度、组成和横向压力条件下，可视化由胆固醇和二棕榈酰磷脂酰胆碱组成的脂质单层中共存的流体相。在胆固醇约为 30 mol%的临界组成下，将平均分子面积降低到每个分子低于 a(c) [unk]50 A(2)迫使二元混合物通过临界点，其中单层变得均匀。在略高于该临界面积的 10%的分子面积下，我们观察到从具有圆形形状的液体域到具有较不对称形状的域的形状转变。由于单层的光化学反应，光也可以触发形状转变和临界形状波动。因此，脂质域的形状波动可用于感测空气-水界面处的化学事件。
