title: Electrophoresis of two spheres: Influence of double layer and van der Waals interactions.
abstract: Considering recent applications of electrophoresis conduced in nanoscaled devices, where particle-particle interaction can play a role, we studied for the first time the electrophoresis of two rigid spheres along their center line, taking account of the hydrodynamic, electric, and van der Waals interactions between them. Under the conditions of constant surface potential and surface charge density, the influences of the level of surface potential/charge density, the bulk salt concentration, and the particle-particle distance on their electrokinetic behaviors are examined. Numerical simulation reveals that these behaviors are much more complicated and interesting than those of isolated particles. In particular, we show that care must be taken in choosing an appropriate particle concentration in relevant experiment to avoid obtaining unreliable mobility data.
authors.affiliation: Department of Mathematics, Tamkang University, Tamsui, Taipei 25137, Taiwan.
authors.forename: Shiojenn
authors.initials: S
authors.lastname: Tseng
authors.affiliation: Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Chih-Hua
authors.initials: CH
authors.lastname: Huang
authors.affiliation: Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan. Electronic address: jphsu@ntu.edu.tw.
authors.forename: Jyh-Ping
authors.initials: JP
authors.lastname: Hsu
mesh_terms: D003198:Computer Simulation; D004586:Electrophoresis; D057446:Hydrodynamics; D008956:Models, Chemical; D010316:Particle Size; D055672:Static Electricity; D013499:Surface Properties
keywords: Electric double layer force; Electrophoresis; Two spheres; Van der Waals force