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arXiv · 2502.11319

Diffuse-charge dynamics across a capacitive interface in a DC electric field

Shuozhen Zhao·Bhavya Balu·Zongxin Yu·Michael J. Miksis·Petia M. Vlahovska
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Abstract

Cells and cellular organelles are encapsulated by nanometrically thin membranes whose main component is a lipid bilayer. In the presence of electric fields, the ion-impermeable lipid bilayer acts as a capacitor and supports a potential difference across the membrane. We analyze the charging dynamics of a planar membrane separating bulk solutions with different electrolyte concentrations upon the application of an applied uniform DC electric field. The membrane is modeled as a zero-thickness capacitive interface. The evolution of the electric potential and ions distributions in the bulk are solved for using the Poisson-Nernst-Planck (PNP) equations. Asymptotic solutions are derived in the limit of thin Debye layers and weak fields (compared to the thermal electric potential).

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Shuozhen Zhao, Bhavya Balu, Zongxin Yu, Michael J. Miksis, Petia M. Vlahovska. 2025-02-17. Diffuse-charge dynamics across a capacitive interface in a DC electric field. https://arxiv.org/abs/2502.11319

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