Biophysics Graduate Group, College of Biological Sciences, University of California, Davis, California 95616, USA.
Langmuir. 2010 Jul 6;26(13):10415-8. doi: 10.1021/la1012268.
Herein we develop a sample preparation approach that enables the use of supported lipid bilayers for the quantitative study of the influence of ethanol (0-20 vol %) on the phase behavior of phospholipid (DPPC)/sterol (ergosterol, 0-20 mol %) bilayers. Three coexisting phases were observed with tapping-mode atomic force microscopy: gel (L(beta)'), liquid-ordered (L(o)), and interdigitated (L(beta)'I). High-resolution imaging permitted the construction of a refined phase diagram for DPPC/ergosterol/ethanol and the observation of L(o)-L(beta)' phase separation that has not been observed using optical techniques. Our results quantitatively show the concentration regime where ergosterol protects the membrane by reducing the membrane fraction that is interdigitated in the presence of ethanol.
在此，我们开发了一种样品制备方法，使我们能够使用支撑脂质双层来定量研究乙醇（0-20 体积%）对磷脂（DPPC）/固醇（麦角固醇，0-20 摩尔%）双层相行为的影响。通过敲击模式原子力显微镜观察到三种共存相：凝胶（L(beta) '）、液晶有序（L(o)）和交错（L(beta)'I）。高分辨率成像允许构建 DPPC/麦角固醇/乙醇的精细相图，并观察到使用光学技术未观察到的 L(o)-L(beta)'相分离。我们的结果定量地显示了麦角固醇通过减少在乙醇存在下交错的膜部分来保护膜的浓度范围。
