Electrokinetic transport of a slender particle through a pore

Abstract

A theoretical model has been developed for estimating the electrokinetic velocity of a slender cylindrical particle in a host pore. Both the particle and the pore wall bear surface charge. The pore-wall charge leads to electro-osmotic flow of the pore fluid. As a result, the particle moves under the combined influence of an electrical force and a hydrodynamic drag. These forces in turn are affected by the particle–pore electrical double layer interaction, when the ionic strength of the pore solution and/or the particle–pore-wall separation are small. The model takes into account these factors controlling the particle transport, revealing design considerations for electrokinetic colloid separation processes.