Minimalist molecular model for nanopore selectivity.

Dr. Mauricio Carrillo-Tripp, PhD
Dr. Mauricio Carrillo-Tripp, PhD
Biomolecular Diversity Laboratory, Cinvestav
Associate Profesor
Computational Biophysics
Irapuato, Guanajuato | México

Phys Rev Lett 2004 Oct 14;93(16):168104. Epub 2004 Oct 14.

Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Avenida Universidad 1001, 62210 Cuernavaca, Morelos, México.

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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October 2004
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