Current fluctuations in nanopores: the effects of electrostatic and hydrodynamic interactions

TL;DR

This study uses simulations to examine how hydrodynamic interactions influence ionic current fluctuations in nanopores, revealing that these interactions do not alter the power spectrum shape within the studied frequency range.

Contribution

It demonstrates through simulations that hydrodynamic interactions do not impact the power spectral density of nanopore currents in the examined frequency range.

Findings

Power-law dependence of power spectral density at low frequency

Exponent depends on ion density

Hydrodynamic interactions do not affect the spectrum shape

Abstract

Using nonequilibrium Langevin dynamics simulations of an electrolyte with explicit solvent particles, we investigate the effect of hydrodynamic interactions on the power spectrum of ionic nanopore currents. At low frequency, we find a power-law dependence of the power spectral density, with an exponent depending on the ion density. Surprisingly, however, the exponent is not affected by the presence of the neutral solvent particles. We conclude that hydrodynamic interactions do not affect the shape of the power spectrum in the frequency range studied.