非接触式扫描离子电导显微镜技术在探测活体细胞表面微结构中的应用

Non-contact scanning ion conductance microscopy for high-resolution morphological imaging of live cells

扫描离子电导显微镜技术是在纳米尺度进行非导电的生物样品成像的一种新型扫描探针显微镜技术。通过成功制备扫描离子电导显微镜扫描探测用纳米尺度玻璃微探针,对其进行了功能性评估;而后通过绘制探针-样品接近曲线,阐述了扫描离子电导显微镜技术实现非接触高分辨率探测的工作原理;最后采用该显微镜技术对导电标准样品及活体肾上皮A6细胞进行了表面形貌扫描成像,并与A6细胞表面形貌的扫描电镜图像进行了对照。结果表明,扫描离子电导显微镜技术不仅可实现导电样品的扫描成像,而且适宜于在生理条件下、非接触式地研究活体细胞表面的三维形貌,从而为人们深入研究细胞表面微观结构与生理功能提供了全新的技术手段。

As a new kind of scanning probe microscopy, scanning ion conductance microscopy （SICM） is designed for imaging non-conducting biological sample at the nanometer scale. Firstly, nanometer scale glass micropipettes were pulled successfully, and were functionally evaluated. Secondly, a micropipette-sample approaching curve was obtained for describing the working principle of SICM. Finally, SICM was used to scan the morphology of a conductive standard sample and live renal epithelial A6 cells. The topography of A6 cells monolayer was verified with Scanning Electron Microscopy （SEM） observation. As a result, non-contact SICM can be used not only for scanning conductive samples, but also for acquiring 3D morphological image of non-conducting living cells. It provides a powerful tool for in-depth studying the relationship between the cell membrane mierostructures and their physiological functions.