Active dynamics of linear chains and rings in porous media

Abstract

To understand the dynamical and conformational properties of deformable active agents in porous media, we computationally investigate the dynamics of linear chains and rings made of active Brownian monomers. In porous media, flexible linear chains and rings always migrate smoothly and undergo activity-induced swelling. However, semiflexible linear chains though navigate smoothly, shrink at lower activities, followed by swelling at higher activities, while semiflexible rings exhibit a contrasting behavior. Semiflexible rings shrink, get trapped at lower activities, and escape at higher activities. This demonstrates how activity and topology interplay and control the structure and dynamics of linear chains and rings in porous media. We envision that our study will shed light on understanding the mode of transport of shape-changing active agents in porous media.

Self-Organized States from Solutions of Active Ring Polymers in Bulk and under Confinement

“…It is thus intriguing to observe similar features given the numerous differences. Further, a recent work 57 shows clustering emerges also if different self-propulsion models at lower dimensionality are considered; at variance with this paper, the activity-induced clustering is there hindered by the polymer connectivity and topology. Our computational study demonstrates the possibility of realizing self-organizing active fluids with polymers, where the peculiar "two population" fluid emerges thanks to the deformability and elasticity of the rings, that can switch between squeezed, elongated and swollen, disk-like configurations reversibly, without changing their topology.…”

Escape dynamics of active ring polymers in a cylindrical nanochannel

“…The passive chain, however, is in constant fugitive motion with increased velocity at the tail end of the escape. As reported in the literature, 65,78 the effect of the bending rigidity of chains may be an essential issue that cannot be ignored and deserves further attention. In addition, Laradji et al have found the collective vortical motion and vorticity reversals of self-propelled particles on circularly patterned substrates, 79 which suggests that in addition to simple confinement, more complex environments may also lead to the understanding of new dynamics.…”

Forced and spontaneous translocation dynamics of a semiflexible active polymer in two dimensions

“…Moreover, the transport of macromolecules in complex, crowded environments is a fundamental issue to understand the diverse relevant processes happening in densely packed biological and environmental settings. 50–53 In particular, diffusion dynamics of active entities through disordered, porous environments has gained increasing appreciation. It has been found that the rigidity of active polymers is one of the crucial factors in determining the efficient navigation in porous environments.…”