title: Mobility reversal of polyelectrolyte-grafted colloids in monovalent salt solutions.
abstract: We present molecular dynamics simulations on the electrophoresis of a negative colloid grafted with positive polyelectrolytes. Net-neutral colloids show a varying mobility in monovalent salt. For colloids with negative net charge the mobility is negative at low and positive at high salt concentrations. This mobility reversal is an electrokinetic effect, and thus different from that observed in multivalent salt. Our results agree with numerical calculations based on the Darcy-Brinkman formalism, with which we predict the mobility reversal to also occur for experimentally accessible colloids.
authors.affiliation: Institut für Computerphysik, Universität Stuttgart, Allmandring 3, D-70569 Stuttgart, Germany.
authors.forename: Shervin
authors.initials: S
authors.lastname: Raafatnia
authors.affiliation: Institut für Computerphysik, Universität Stuttgart, Allmandring 3, D-70569 Stuttgart, Germany.
authors.forename: Owen A
authors.initials: OA
authors.lastname: Hickey
authors.affiliation: Institut für Computerphysik, Universität Stuttgart, Allmandring 3, D-70569 Stuttgart, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Holm