Bionanotechnology and Nanomedicine Laboratory, Department of Chemistry and Nano-science Center, University of Copenhagen, Universitetsparken 5, DK-2100, Copenhagen, Denmark.
Nanotechnology. 2012 Oct 19;23(41):415102. doi: 10.1088/0957-4484/23/41/415102. Epub 2012 Sep 25.
The perspectives offered by vertical arrays of nanowires for biosensing applications in living cells depend on the access of individual nanowires to the cell interior. Recent results on electrical access and molecular delivery suggest that direct access is not always obtained. Here, we present a generic approach to directly visualize the membrane conformation of living cells interfaced with nanowire arrays, with single nanowire resolution. The method combines confocal z-stack imaging with an optimized cell membrane labelling strategy which was applied to HEK293 cells interfaced with 2-11 μm long and 3-7 μm spaced nanowires with various surface coatings (bare, aminosilane-coated or polyethyleneimine-coated indium arsenide). We demonstrate that, for all commonly used nanowire lengths, spacings and surface coatings, nanowires generally remain enclosed in a membrane compartment, and are thereby not in direct contact with the cell interior.
用于活细胞中生物传感应用的纳米线垂直阵列所提供的观点取决于各个纳米线进入细胞内部的情况。最近关于电接触和分子传递的结果表明，并不总是能够直接获得这种接触。在这里，我们提出了一种通用方法，可直接观察与纳米线阵列连接的活细胞膜的构象，具有单纳米线分辨率。该方法将共聚焦 z 堆叠成像与优化的细胞膜标记策略相结合，该策略应用于与 2-11μm 长和 3-7μm 间隔的纳米线连接的 HEK293 细胞，这些纳米线具有各种表面涂层（裸、氨基硅烷涂层或聚乙烯亚胺涂层砷化铟）。我们证明，对于所有常用的纳米线长度、间距和表面涂层，纳米线通常仍被封闭在细胞膜隔室中，因此不会与细胞内部直接接触。
