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arXiv · 1410.1862

Ionic current inversion in pressure-driven polymer translocation through nanopores

Sahin Buyukdagli·Ralf Blossey·T. Ala-Nissila
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Abstract

We predict streaming current inversion with multivalent counterions in hydrodynamically driven polymer translocation events from a correlation-corrected charge transport theory including charge fluctuations around mean-field electrostatics. In the presence of multivalent counterions, electrostatic many-body effects result in the reversal of the DNA charge. The attraction of anions to the charge-inverted DNA molecule reverses the sign of the ionic current through the pore. Our theory allows for a comprehensive understanding of the complex features of the resulting streaming currents. The underlying mechanism is an efficient way to detect DNA charge reversal in pressure-driven translocation experiments with multivalent cations.

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Sahin Buyukdagli, Ralf Blossey, T. Ala-Nissila. 2015-02-01. Ionic current inversion in pressure-driven polymer translocation through nanopores. https://doi.org/10.1103/physrevlett.114.088303

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