Diffusiophoretic Brownian dynamics: characterization of hydrodynamic effects for an active chemoattractive polymer

TL;DR

This paper introduces an optimized phoretic Brownian dynamics method to simulate chemoattractive polymers, revealing how hydrodynamics influence polymer conformations and collapse times, enabling studies of longer polymers.

Contribution

The work develops a modified phoretic Brownian dynamics approach that accurately incorporates explicit solvent effects for chemoattractive polymers, allowing longer simulations and detailed hydrodynamic analysis.

Findings

Hydrodynamics affect polymer collapse times non-trivially.

Chemoattractive polymers transition to globular states with activity.

Radius of gyration and relaxation time grow non-monotonously with polymer length.

Abstract

The phoretic Brownian dynamics method is shown here to be an effective approach to simulate the properties of colloidal chemophoretic based systems. The method is then optimized to allow for the comparison with results from multiparticle collision dynamics, a hydrodynamic method with explicit solvent, which can also be employed in the case of chemoattractive polymers. In order to obtain a good match of the conformational equilibrium properties of the models without and with explicit solvent, we propose a modified version of the phoretic Brownian dynamics accounting for the explicit solvent induced swelling. In the presence of activity, chemoattractive polymers show a transition to a compact globular state and hydrodynamics have a non-trivial influence in the polymer collapse times. The phoretic Brownian method can then be applied to much longer polymers, which allows the observation of a non-monotonous growth of both, the radius of gyration and the relaxation time with polymer length, for such chemoattractive active polymers.