Folding and unfolding kinetics of a single semiflexible polymer

TL;DR

This paper presents a theoretical and simulation study of the folding and unfolding kinetics of a single semiflexible polymer, revealing how domain size affects dissipation and providing scaling exponents for relaxation steps.

Contribution

It introduces a theoretical model for polymer folding/unfolding kinetics and validates it with Langevin dynamics simulations, including effects of hydrodynamic interactions.

Findings

Growth rate decreases with larger collapsed domains.

Scaling exponents of 1/8 and 1/4 for disentanglement and relaxation.

Good agreement between theory and simulations.

Abstract

We theoretically investigate the kinetics of the folding transition of a single semiflexible polymer. In the folding transition, the growth rate decrease with an increase in the number of monomers in a collapsed domain, suggesting that the main contribution to dissipation is from the motion of the domain. In the unfolding transition, dynamic scaling exponents, 1/8 and 1/4, were determined for disentanglement and relaxation steps, respectively. We performed Langevin dynamics simulations to test our theory. It is found that our theory is in good agreement with simulations. We also propose the kinetics of the transitions in the presence of the hydrodynamic interaction.