Influences of streaming potential on cross stream migration of flexible polymer molecules in nanochannel flows

Abstract

We execute augmented Brownian dynamics (BD) simulation studies to show that the migration of flexible polyelectrolyte chains through nanochannels may be strongly governed by a complicated interplay between the electroviscous effects, near-wall interaction mechanisms, and diffusophoretic transport due to thermal gradients prevailing in the system. We further illustrate that in presence of mutually opposing pressure-driven and electro-osmotic transport and with an optimal choice of the ratio of the strength of these two flow fields, the electroviscous effects may turn out to be immensely consequential in strengthening the effective confinement of the polyelectrolyte. This, in turn may permit in achieving important biophysical feats that are otherwise obtainable only through significantly reduced nanochannel dimensions.