Institute for Theoretical Physics, Georg-August-Universität, 37077 Göttingen, Germany.
Langmuir. 2013 Apr 2;29(13):4335-49. doi: 10.1021/la400119e. Epub 2013 Mar 21.
Exposition of unilamellar vesicles to attractive surfaces is a frequently used way to create supported lipid bilayers. Although this approach is known to produce continuous supported bilayer coatings, the mechanism of their formation and its dependence on factors like surface interaction and roughness or membrane tension as well as the interplay between neighboring vesicles or the involvement of preadsorbed bilayer patches are not well understood. Using dissipative particle dynamics simulations, we assess different mechanisms of vesicle spreading on attractive surfaces, placing special emphasis on the orientation of the resulting bilayer. Making use of the universality of collective phenomena in lipid membranes, we employed a solvent-free coarse-grained model, enabling us to cover the relatively large system sizes and time scales required. Our results indicate that one can control the mechanism of vesicle spreading by tuning the strength and range of the interactions with the substrate as well as the surface's roughness, resulting in a switch from a predominant inside-up to an outside-up orientation of the created supported bilayer.
将单层囊泡暴露于有吸引力的表面是一种常用的方法来制备支撑脂质双层。尽管这种方法已知会产生连续的支撑双层涂层，但它们的形成机制及其对表面相互作用和粗糙度或膜张力等因素的依赖性，以及相邻囊泡之间的相互作用或预吸附双层斑块的参与情况，都不是很清楚。我们使用耗散粒子动力学模拟评估了囊泡在有吸引力的表面上扩散的不同机制，特别强调了所得双层的取向。利用脂质膜中集体现象的普遍性，我们采用了无溶剂的粗粒化模型，从而能够覆盖所需的较大系统尺寸和时间尺度。我们的结果表明，可以通过调节与基底的相互作用的强度和范围以及表面的粗糙度来控制囊泡扩散的机制，从而导致从主要的内翻到外翻的创建支撑双层的取向发生转变。
