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arXiv 1102.4513cond-mat.softphysics.bio-ph
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电场中的平面脂双层:膜不稳定性、流场和电阻抗

A planar lipid bilayer in an electric field: membrane instability, flow field and electrical impedance

Falko Ziebert, David Lacoste

摘要:

对于许多生物技术应用,更好地理解电场对脂质膜产生的影响将是有用的。本文综述了在正常直流或交流电场中平面脂质膜及其周围电解质的静电性质的几个方面。在平面几何形状中,电动方程的分析可以进行得相当远,允许解析地表征德拜层中的电荷积累的稳态和动态,这是由电场的应用引起的。对于在一个外加直流电场的导电膜,我们表征的弹性模量的修正,膜波动不稳定性的外观和相关的流量是建立在膜附近。对于在一个应用的AC电场中的膜,我们解析地从基本的电动力学方程推导出阻抗。我们讨论了不同的相关影响,由于膜的电导率或由于体扩散系数的离子。特别感兴趣的是膜仅对一种类型的离子具有选择性导电性的情况。这些结果,及其未来的扩展,应该是有用的阻抗谱数据的解释,用于表征,例如,离子通道嵌入在平面双层。

英文摘要:

For many biotechnological applications it would be useful to better understand the effects produced by electric fields on lipid membranes. This review discusses several aspects of the electrostatic properties of a planar lipid membrane with its surrounding electrolyte in a normal DC or AC electric field. In the planar geometry, the analysis of electrokinetic equations can be carried out quite far, allowing to characterize analytically the steady state and the dynamics of the charge accumulation in the Debye layers, which results from the application of the electric field. For a conductive membrane in an applied DC electric field, we characterize the corrections to the elastic moduli, the appearance of a membrane undulation instability and the associated flows which are built up near the membrane. For a membrane in an applied AC electric field, we analytically derive the impedance from the underlying electrokinetic equations. We discuss different relevant effects due to the membrane conductivity or due to the bulk diffusion coefficients of the ions. Of particular interest is the case where the membrane has selective conductivity for only one type of ion. These results, and future extensions thereof, should be useful for the interpretation of impedance spectroscopy data used to characterize e.g. ion channels embedded in planar bilayers.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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