Simulation of pH-Regulated Electrokinetic Ion Transport in Nanopores with Polyelectrolyte Brushes

Nanopores with polyelectrolyte brushes in a pH-regulated ion channel have been simulated. Electrokinetic ion transport was studied taking account of the effects of pH, presence of multiple ionic species and bulk ionic concentration. A continuum-based model that composed of coupled Poisson-Nernst- Planck equations for the ionic mass transport with electric potential, and Navier-Stokes and Brinkman equations for the fluid flow, were employed. Our results demonstrate that the bulk ionic concentration and pH together can greatly influence the charge of the polyelectrolyte brushes, the distribution of electric potential in the nanopore and also the fluid flow is sensitive to the pH variations.