Rectification of polymer translocation through nanopores by chiral and nonchiral active particles

TL;DR

This study investigates how active particles, both chiral and nonchiral, influence the unbiased translocation of a flexible polymer through a nanopore, revealing a transition between two rectified states driven by active noise and steric effects.

Contribution

It introduces a simulation-based analysis of polymer translocation affected by active particles, highlighting a transition between rectified states due to particle activity and chirality.

Findings

Transition between cis-to-trans and trans-to-cis states observed.

Translocation time sharply increases at the transition point.

System parameters like activity, area fraction, and chirality influence the transition.

Abstract

We study unbiased translocation of a flexible polymer chain through a membrane pore under the influence of active noise and steric exclusion using Langevin dynamics simulations. The active noise is incorporated by introducing nonchiral and chiral active particles on one or both sides of the membrane. Translocation of the polymer into either side of the pore is assisted by an effective pulling due to particle activity and is hindered by an effective pushing due to steric repulsions between the polymer and active particles. As a result of the competition between these effective forces, we find a transition between two rectified ({\em cis}-to-{\em trans} and {\em trans}-to-{\em cis}) states. This transition is identified by a sharp increase of translocation time. It varies depending on the system parameters such as particle activity, area fraction and chirality whose effects are explored in this work.