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An electro-hydrodynamics-based model for the ionic conductivity of solid-state nanopores during DNA translocation.

ABSTRACT: A solid-state nanopore can be used to sense DNA (or other macromolecules) by monitoring ion-current changes that result from translocation of the molecule through the pore. When transiting a nanopore, the highly negatively charged DNA interacts with a nanopore both electrically and hydrodynamically, causing a current blockage or a current enhancement at different ion concentrations. This effect was previously characterized using a phenomenological model that can be considered as the limit of the electro-hydrodynamics model presented here. We show theoretically that the effect of surface charge of a nanopore (or electro-osmotic effect) can be equivalently treated as modifications of electrophoretic mobilities of ions in the pore, providing an improved physical understanding of the current blockage (or enhancement).

SUBMITTER: Luan B

PROVIDER: S-EPMC3681960 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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An electro-hydrodynamics-based model for the ionic conductivity of solid-state nanopores during DNA translocation.

Luan Binquan B Stolovitzky Gustavo G

Nanotechnology 20130412 19

A solid-state nanopore can be used to sense DNA (or other macromolecules) by monitoring ion-current changes that result from translocation of the molecule through the pore. When transiting a nanopore, the highly negatively charged DNA interacts with a nanopore both electrically and hydrodynamically, causing a current blockage or a current enhancement at different ion concentrations. This effect was previously characterized using a phenomenological model that can be considered as the limit of the ...[more]

PMID: 23579206

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