Minimalist molecular model for nanopore selectivity.

Mauricio Carrillo-Tripp; Humberto Saint-Martin; Iván Ortega-Blake

doi:10.1103/physrevlett.93.168104

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Minimalist molecular model for nanopore selectivity.

Mauricio Carrillo-Tripp·Humberto Saint-Martin·Iván Ortega-Blake

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Abstract

Using a simple model it is shown that the cost of constraining a hydrated potassium ion inside a narrow nanopore is smaller than the cost of constraining the smaller hydrated sodium ion. The former allows for a greater distortion of its hydration shell and can therefore maintain a better coordination. We propose that in this way the larger ion can go through narrow pores more easily. This is relevant to the molecular basis of ion selective nanopores and since this mechanism does not depend on the molecular details of the pore, it could also operate in all sorts of nanotubes, from biological to synthetic.

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Cations, Monovalent Cell Membrane Models, Biological Models, Chemical Models, Molecular Nanotechnology Potassium Potassium Channels Sodium Sodium Channels Thermodynamics Journal Article Research Support, Non-U.S. Gov't

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Mauricio Carrillo-Tripp, Humberto Saint-Martin, Iván Ortega-Blake. 2004-10-14. Minimalist molecular model for nanopore selectivity.. https://doi.org/10.1103/physrevlett.93.168104

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