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Self-energy limited ion transport in sub-nanometer channels

Douwe Jan Bonthuis·Jingshan Zhang·Breton Hornblower·Jerome Mathe·Boris I. Shklovskii·Amit Meller
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Abstract

The current-voltage characteristics of the alpha-Hemolysin protein pore during the passage of single-stranded DNA under varying ionic strength, C, are studied experimentally. We observe strong blockage of the current, weak super-linear growth of the current as a function of voltage, and a minimum of the current as a function of C. These observations are interpreted as the result of the ion electrostatic self-energy barrier originating from the large difference in the dielectric constants of water and the lipid bilayer. The dependence of DNA capture rate on C also agrees with our model.

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Douwe Jan Bonthuis, Jingshan Zhang, Breton Hornblower, Jerome Mathe, Boris I. Shklovskii, Amit Meller. 2006-07-19. Self-energy limited ion transport in sub-nanometer channels. https://doi.org/10.1103/physrevlett.97.128104

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