Electrophoresis of a soft toroid of nonuniform structure

Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan.
Colloids and surfaces B: Biointerfaces (Impact Factor: 4.29). 05/2012; 98:36-42. DOI: 10.1016/j.colsurfb.2012.04.019
Source: PubMed

ABSTRACT The electrophoresis of a nonuniformly structured soft particle is modeled theoretically by considering an isolated soft toroid comprising a rigid core and a polyelectrolyte layer with exponential segment distribution. The influences of the thickness of double layer, and the fixed charge density, the friction coefficient, the uniformity, and the thickness of the polyelectrolyte layer on the electrophoresis behavior of the toroid are examined. We show that for a specified fixed charge density, the electrophoresis mobility of the toroid increases with increasing double layer thickness, and the higher that density the larger the mobility. The thicker the polyelectrolyte layer and/or more uniform the segment distribution of that layer the higher the fixed charge density, yielding a larger mobility. The thicker the double layer the more significant is the influence of the polyelectrolyte layer structure of a toroid on its mobility.

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