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Molecular control of ionic conduction in polymer nanopores.

ABSTRACT: Polymeric nanopores show unique transport properties and have attracted a great deal of scientific interest as a test system to study ionic and molecular transport at the nanoscale. By means of all-atom molecular dynamics, we simulated the ion dynamics inside polymeric polyethylene terephthalate nanopores. For this purpose, we established a protocol to assemble atomic models of polymeric material into which we sculpted a nanopore model with the key features of experimental devices, namely a conical geometry and a negative surface charge density. Molecular dynamics simulations of ion currents through the pore show that the protonation state of the carboxyl group of exposed residues have a considerable effect on ion selectivity, by affecting ionic densities and electrostatic potentials inside the nanopores. The role of high concentrations of Ca2+ ions was investigated in detail.

SUBMITTER: Cruz-Chu ER

PROVIDER: S-EPMC2907245 | biostudies-literature | 2009

REPOSITORIES: biostudies-literature

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Molecular control of ionic conduction in polymer nanopores.

Cruz-Chu Eduardo R ER Ritz Thorsten T Siwy Zuzanna S ZS Schulten Klaus K

Faraday discussions 20090101

Polymeric nanopores show unique transport properties and have attracted a great deal of scientific interest as a test system to study ionic and molecular transport at the nanoscale. By means of all-atom molecular dynamics, we simulated the ion dynamics inside polymeric polyethylene terephthalate nanopores. For this purpose, we established a protocol to assemble atomic models of polymeric material into which we sculpted a nanopore model with the key features of experimental devices, namely a coni ...[more]

PMID: 20334094

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