Partitioning and conformational behavior of polyelectrolytes confined in a cylindrical pore

Abstract

We study the behavior of a uniformly charged polyelectrolyte confined in a circular cylindrical pore with constant surface potentials. From Green's function theory with an effective step-length renormalized by monomer-monomer interactions, the partition coefficient and associated chain conformations are predicted in a variety of situations. Depending upon the ionic strength of surrounding fluids, the polyelectrolyte conformation may be stretched and follow a self-avoiding walk, yielding a significant reduction in the partition coefficient compared to the ideal chain result. The monomer-monomer interaction is found to be as important as the polymer-pore interaction in determining the partitioning behavior, especially in the long-chain regime, due to the characteristics of confined spates.