title: Minimalist molecular model for nanopore selectivity.
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.
authors.affiliation: Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Avenida Universidad 1001, 62210 Cuernavaca, Morelos, México.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Carrillo-Tripp
authors.forename: Humberto
authors.initials: H
authors.lastname: Saint-Martin
authors.forename: Iván
authors.initials: I
authors.lastname: Ortega-Blake
mesh_terms: D002414:Cations, Monovalent / Q000737:chemistry / Q000378:metabolism; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D008954:Models, Biological; D008956:Models, Chemical; D008958:Models, Molecular; D036103:Nanotechnology / Q000379:methods; D011188:Potassium / Q000737:chemistry* / Q000378:metabolism; D015221:Potassium Channels / Q000737:chemistry* / Q000378:metabolism; D012964:Sodium / Q000737:chemistry* / Q000378:metabolism; D015222:Sodium Channels / Q000737:chemistry* / Q000378:metabolism; D013816:Thermodynamics
chemical_list: D002414:Cations, Monovalent; D015221:Potassium Channels; D015222:Sodium Channels; D012964:Sodium; D011188:Potassium