Gliss C, Clausen-Schaumann H, Günther R, Odenbach S, Randl O, Bayerl T M
Institut für Physik EP-5, Universität Würzburg, Germany.
Biophys J. 1998 May;74(5):2443-50. doi: 10.1016/S0006-3495(98)77952-4.
The geometry of domains in phospholipid bilayers of binary (1:1) mixtures of synthetic lecithins with a difference in chain length of four methylene groups has been studied by two independent, direct and complementary methods. Grazing incidence diffraction of neutrons provided gel domain sizes of less than 10 nm in both the gel and the coexistence phase of the mixture, while no domains were detected for the fluid phase. For the coexistence region, the neutron data suggest that domains grow in number rather than in size with decreasing temperature. Atomic force microscopy was used to study gel phase size and shape of the domains. The domains imaged by atomic force microscopy exhibit a rather irregular shape with an average size of 10 nm, thus confirming the neutron results for this phase. The good agreement between atomic force microscopy and neutron results, despite the completely different nature of their observables, has potential for the future development of refined models for the interpretation of neutron data from heterogeneous membranes in terms of regularly spaced and spatially extended scatterers.
通过两种独立、直接且互补的方法，研究了链长相差四个亚甲基的合成卵磷脂二元（1:1）混合物在磷脂双层中的结构域几何形状。中子掠入射衍射表明，在混合物的凝胶相和共存相中，凝胶结构域尺寸均小于10nm，而在流体相中未检测到结构域。对于共存区域，中子数据表明，随着温度降低，结构域数量增加而非尺寸增大。利用原子力显微镜研究了凝胶相结构域的尺寸和形状。原子力显微镜成像的结构域呈现出相当不规则的形状，平均尺寸为10nm，从而证实了该相的中子结果。尽管原子力显微镜和中子结果的可观测性质完全不同，但二者结果吻合良好，这为未来开发精细模型奠定了基础，该模型可根据规则间隔和空间扩展的散射体来解释来自异质膜的中子数据。
