Home > Research > Publications & Outputs > Coulomb blockade model of permeation and select...

Electronic data

Links

Text available via DOI:

View graph of relations

Coulomb blockade model of permeation and selectivity in biological ion channels

Research output: Contribution to journalJournal articlepeer-review

Published
Article number083021
<mark>Journal publication date</mark>11/08/2015
<mark>Journal</mark>New Journal of Physics
Issue number8
Volume17
Number of pages15
Publication StatusPublished
<mark>Original language</mark>English

Abstract

Biological ion channels are protein nanotubes embedded in, and passing through, the bilipid membranes of cells. Physiologically, they are of crucial importance in that they allow ions to pass into and out of cells, fast and efficiently, though in a highly selective way. Here we show that the conduction and selectivity of calcium/sodium ion channels can be described in terms of ionic Coulomb blockade in a simplified electrostatic and Brownian dynamics model of the channel. The Coulomb blockade phenomenon arises from the discreteness of electrical charge, the strong electrostatic interaction, and an electrostatic exclusion principle. The model predicts a periodic pattern of Ca2+ conduction versus the fixed charge Qf at the selectivity filter (conduction bands) with a period equal to the ionic charge. It thus provides provisional explanations of some observed and modelled conduction and valence selectivity phenomena, including the anomalous mole fraction effect and the calcium conduction bands. Ionic Coulomb blockade and resonant conduction are similar to electronic Coulomb blockade and resonant tunnelling in quantum dots. The same considerations may also be applicable to other kinds of channel, as well as to charged artificial nanopores.

Bibliographic note

This is an author-created, un-copyedited version of an article accepted for publication/published in New Journal of Physics. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at doi:10.1088/1367-2630/17/8/083021