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arXiv · 1507.04160

Steric modulation of ionic currents in DNA translocation through nanopores

Valerio Mazzone·Simone Melchionna·Umberto Marini Bettolo Marconi
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Abstract

Ionic currents accompanying DNA translocation strongly depend on molarity of the electrolyte solution and the shape and surface charge of the nanopore. By means of the Poisson-Nernst-Planck equations it is shown how conductance is modulated by the presence of the DNA intruder and as a result of competing electrostatic and confinement factors. The theoretical results reproduce quantitatively the experimental ones and are summarized in a conductance diagram that allows distinguishing the region of reduced conductivity from the region of enhanced conductivity as a function of molarity and the pore dimension.

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Valerio Mazzone, Simone Melchionna, Umberto Marini Bettolo Marconi. 2015-07-15. Steric modulation of ionic currents in DNA translocation through nanopores. https://doi.org/10.1007/s10955-014-1159-8

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