Terpitz Ulrich, Sukhorukov Vladimir L, Zimmermann Dirk
Department of Biophysical Chemistry, Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
Assay Drug Dev Technol. 2013 Feb;11(1):9-16. doi: 10.1089/adt.2012.455. Epub 2012 Sep 20.
Functional access to membrane proteins, for example, ion channels, of individual cells is an important prerequisite in drug discovery studies. The highly sophisticated patch-clamp method is widely used for electrogenic membrane proteins, but is demanding for the operator, and its automation remains challenging. The dielectrophoretically-accessed, intracellular membrane-potential measurement (DAIMM) method is a new technique showing high potential for automation of electrophysiological data recording in the whole-cell configuration. A cell suspension is brought between a mm-scaled planar electrode and a μm-scaled tip electrode, placed opposite to each other. Due to the asymmetric electrode configuration, the application of alternating electric fields (1-5 MHz) provokes a dielectrophoretic force acting on the target cell. As a consequence, the cell is accelerated and pierced by the tip electrode, hence functioning as the internal (working) electrode. We used the light-gated cation channel Channelrhodopsin-2 as a reporter protein expressed in HEK293 cells to characterize the DAIMM method in comparison with the patch-clamp technique.
例如，对于单个细胞的膜蛋白（如离子通道）进行功能研究是药物发现研究中的一个重要前提。高度复杂的膜片钳技术广泛应用于电生膜蛋白研究，但对操作人员要求较高，其自动化仍然具有挑战性。介电泳辅助细胞内膜电位测量（DAIMM）方法是一种新技术，在全细胞配置下电生理数据记录自动化方面显示出很高的潜力。将细胞悬液置于相互相对的毫米级平面电极和微米级尖端电极之间。由于不对称电极配置，施加交变电场（1-5MHz）会产生作用于目标细胞的介电泳力。结果，细胞被加速并被尖端电极刺穿，从而充当内部（工作）电极。我们使用在HEK293细胞中表达的光门控阳离子通道Channelrhodopsin-2作为报告蛋白，与膜片钳技术相比，对DAIMM方法进行了表征。
