Polymer translocation through nanopore assisted by an environment of active rods

TL;DR

This study combines simulations and theory to analyze how active rods in the environment influence polymer translocation through a nanopore, revealing a crowding effect that accelerates the process and deriving a scaling law for translocation time.

Contribution

It introduces a novel model incorporating active rod-induced forces into translocation dynamics, extending the iso-flux tension propagation theory for active environments.

Findings

Active rods induce crowding, facilitating polymer translocation.

Derived a scaling law for translocation time involving rod length and activity.

Validated theoretical predictions with simulation results.

Abstract

We use a combination of computer simulations and iso-flux tension propagation (IFTP) theory to investigate translocation dynamics of a flexible linear polymer through a nanopore into an environment composed of repulsive active rods in 2D. We demonstrate that the rod activity induces a crowding effect on the polymer, leading to a time-dependent net force that facilitates translocation into the active environment. Incorporating this force into the IFTP theory for pore-driven translocation allows us to characterise translocation dynamics in detail and derive a scaling form for the average translocation time as $\tilde{\tau} \sim \tilde{L}_{\textrm{r}}^{\nu} / \tilde{F}_{\textrm{SP}} $, where $\tilde{L}_{\textrm{r}}$ and $\tilde{F}_{\textrm{SP}}$ are the rod length and self-propelling force acting on the rods, respectively, and $\nu$ is the Flory exponent.