Electrophoretic mobility of a particle covered with an ion-penetrable membrane
Journal
Electrophoresis
Journal Volume
22
Journal Issue
10
Pages
1881-1886
Date Issued
2001
Author(s)
Abstract
The electrophoretic behavior of a planar particle covered by an ion-penetrable membrane, which simulates a biological entity, is investigated. We show that, in general, a point charge model will overestimate the electrophoretic mobility of a particle and the deviation increases with the increase in the concentration of fixed charge and with the decrease in the thickness of membrane layer. As in the case of a point charge model, the present model also predicts a local maximum in the absolute mobility as the thickness of membrane layer varies. If the sizes of counterions of various valences are the same, then the lower the valence of counterions, the larger the mobility, and the larger the counterions, the greater the mobility. The latter is consistent with the experimental observations in the literature. For the level of the concentration of fixed charge examined, the effect of coions on the mobility is negligible.
Subjects
Biocolloids
Electrophoretic mobility
Ion-penetrable membrane
Ionic size
Type
journal article