Effect of Electro-Diffusion Current Flow on Electrostatic Screening in Aqueous Pores

Yang Liu; Jon Sauer; Robert Dutton

doi:10.1063/1.2906327

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arXiv · 0712.2478

Effect of Electro-Diffusion Current Flow on Electrostatic Screening in Aqueous Pores

Yang Liu·Jon Sauer·Robert Dutton

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Abstract

A numerical study within the framework of the Poisson-Nernst-Planck equations is conducted to investigate electrostatic screening of charged bio-molecules within synthetic pores having diameters of at least 10 Debye lengths. We show that with external biases, the bio-molecule charge is only partially screened due to the presence of electrodiffusion current flow. This is considerably different from the equilibrium Debye-Huckel screening behavior and will result in long-range electrostatic interactions. The potential application to direct bio-molecule charge sensing is also discussed.

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Yang Liu, Jon Sauer, Robert Dutton. 2007-12-14. Effect of Electro-Diffusion Current Flow on Electrostatic Screening in Aqueous Pores. https://doi.org/10.1063/1.2906327

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