Institute of Organic and Biomolecular Chemistry, Tammannstrasse 2, 37077 Göttingen, Germany.
ACS Nano. 2011 Sep 27;5(9):6935-44. doi: 10.1021/nn201266e. Epub 2011 Aug 2.
Anodic aluminum oxide (AAO) is a porous material having aligned cylindrical compartments with 55-60 nm diameter pores, and being several micrometers deep. A protocol was developed to generate pore-spanning fluid lipid bilayers separating the attoliter-sized compartments of the nanoporous material from the bulk solution, while preserving the optical transparency of the AAO. The AAO was selectively functionalized by silane chemistry to spread giant unilamellar vesicles (GUVs) resulting in large continuous membrane patches covering the pores. Formation of fluid single lipid bilayers through GUV rupture could be readily observed by fluorescence microscopy and further supported by conservation of membrane surface area, before and after GUV rupture. Fluorescence recovery after photobleaching gave low immobile fractions (5-15%) and lipid diffusion coefficients similar to those found for bilayers on silica. The entrapment of molecules within the porous underlying cylindrical compartments, as well as the exclusion of macromolecules from the nanopores, demonstrate the barrier function of the pore-spanning membranes and could be investigated in three-dimensions using confocal laser scanning fluorescence imaging.
阳极氧化铝（AAO）是一种具有规则圆柱形隔室的多孔材料，其孔径为 55-60nm，深度为数微米。我们开发了一种方案，用于生成贯穿孔的流体脂质双层，将纳滤材料的皮升级隔室与主体溶液分隔开，同时保持 AAO 的光学透明度。AAO 通过硅烷化学选择性功能化，以扩展巨大的单层囊泡（GUV），从而形成覆盖孔的大连续膜片。通过荧光显微镜可以很容易地观察到通过 GUV 破裂形成的流体单层脂质双层，并且在 GUV 破裂前后通过保留膜表面积得到进一步支持。光漂白后荧光恢复给出了低不可移动分数（5-15%）和与在二氧化硅上的双层相似的脂质扩散系数。分子在多孔底层圆柱形隔室中的包封以及大分子从纳米孔中的排除，证明了贯穿孔的膜的屏障功能，并且可以使用共聚焦激光扫描荧光成像在三维中进行研究。
