Effect of Local Binding on Stochastic Transport in Ion Channels
| Autor: | W. A. T. Gibby, I. Kh. Kaufman, Dmitry G. Luchinsky, Peter V. E. McClintock |
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| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Physics
Ionic bonding Coulomb blockade FOS: Physical sciences Type (model theory) Condensed Matter - Soft Condensed Matter Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 01 natural sciences Molecular physics 010305 fluids & plasmas Ion symbols.namesake Pauli exclusion principle Quantum dot Biological Physics (physics.bio-ph) 0103 physical sciences Brownian dynamics Coulomb symbols Soft Condensed Matter (cond-mat.soft) Physics - Biological Physics 010306 general physics |
| Popis: | Ionic Coulomb blockade (ICB) is an electrostatic phenomenon recently discovered in low-capacitance ion channels/nanopores. Depending on the fixed charge that is present, ICB strongly and selectively influences the ease with which a given type of ion can permeate the pore. The phenomenon arises from the discreteness of the charge-carriers, the dielectric self-energy, an electrostatic exclusion principle, and sequential pore neutralization, and it manifests itself strongly for divalent ions (e.g.\ Ca$^{2+}$). Ionic Coulomb blockade is closely analogous to electronic Coulomb blockade in quantum dots. In addition to the non-local 1D Coulomb interaction considered in the standard Coulomb blockade approach, we now propose a correction to take account of the singular part of the attraction to the binding site (i.e.\ local site binding). We show that this correction leads to a geometry-dependent shift of one of the barrierless resonant conduction points M$_0^{CB}$. We also show that local ion-ion repulsion accounts for a splitting of Ca$^{2+}$ profiles observed earlier in Brownian dynamics simulations. 4 pages, 4 figures, 25 references, ICNF2017 Replacement reasons: Some typo are fixed, notation is optimised) |
| Databáze: | OpenAIRE |
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