PDF(Pubmed)
Abstract：
Measurement of cellular resting membrane potential (RMP) is important in understanding ion channels and their role in regulation of cell function across a wide range of cell types. However, methods available for the measurement of RMP (including patch clamp, microelectrodes, and potential-sensitive fluorophores) are expensive, slow, open to operator bias, and often result in cell destruction. We present non-contact, label-free membrane potential estimation which uses dielectrophoresis to determine the cytoplasm conductivity slope as a function of medium conductivity. By comparing this to patch clamp data available in the literature, we have demonstratet the accuracy of this approach using seven different cell types, including primary suspension cells (red blood cells, platelets), cultured suspension cells (THP-1), primary adherent cells (chondrocytes, human umbilical mesenchymal stem cells), and adherent (HeLa) and suspension (Jurkat) cancer cell lines. Analysis of the effect of ion channel inhibitors suggests the effects of pharmaceutical agents (TEA on HeLa; DMSO and neuraminidase on red blood cells) can also be measured. Comparison with published values of membrane potential suggest that the differences between our estimates and values recorded by patch clamp are accurate to within published margins of error. The method is low-cost, non-destructive, operator-independent and label-free, and has previously been shown to allow cells to be recovered after measurement.
摘要：
细胞静息膜电位（RMP）的测量对于理解离子通道及其在多种细胞类型中调节细胞功能的作用很重要。然而,可用于测量RMP的方法(包括膜片钳，微电极，和潜在敏感的荧光团）很昂贵，慢,对操作员偏见开放，并经常导致细胞破坏。我们提出非接触，无标记膜电位估计，使用介电电泳确定细胞质电导率斜率作为介质电导率的函数。通过将其与文献中可用的膜片钳数据进行比较，我们使用七种不同的细胞类型证明了这种方法的准确性，包括原代悬浮细胞（红细胞，血小板)，培养的悬浮细胞（THP-1），原代贴壁细胞(软骨细胞，人脐带间充质干细胞），和粘附(HeLa)和悬浮(Jurkat)癌细胞系。离子通道抑制剂的作用分析表明，还可以测量药物（TEA对HeLa的作用；DMSO和神经氨酸酶对红细胞的作用）。与已发布的膜电位值的比较表明，我们的估计值与膜片钳记录的值之间的差异准确到已发布的误差范围内。该方法成本低，非破坏性的，独立于运营商和无标签，并且先前已显示允许在测量后恢复细胞。
