Ratchet rectification effect on the translocation of a flexible polyelectrolyte chain

Abstract

We report a three dimensional Langevin dynamics simulation of a uniformly charged flexible polyelectrolyte chain, translocating through an asymmetric narrow channel with periodically varying cross sections under the influence of a periodic external electric field. When reflection symmetry of the channel is broken, a rectification effect is observed with a favored direction for the chain translocation. For a given volume of the channel unit and polymer length, the rectification occurs below a threshold frequency of the external periodic driving force. We have also observed that the extent of the rectification varies non-monotonically with increasing molecular weight and the strength of geometric asymmetry of the channel. Observed non-monotonicity of the rectification performance has been interpreted in terms of a competition between two effects arising from the channel asymmetry and change in conformational entropy. An analytical model is presented with predictions consistent with the simulation results.

Document Details

Document Type
Pub Defense Publication
Publication Date
Aug 24, 2016
Source ID
10.1063/1.4961505

Entities

People

  • Debasish Mondal
  • Murugappan Muthukumar

Organizations

  • Air Force Office of Scientific Research
  • National Human Genome Research Institute
  • National Science Foundation
  • University of Massachusetts

Tags

Readers

  • Control Systems Engineering.
  • Materials Science and Engineering.
  • Plasma Physics.