Electrophoresis of a Finite Cylinder along the Axis of a Cylindrical Pore

• Published in: The journal of physical chemistry. B 2002-10, Vol.106 (41), p.10605-10609
• Main Authors: Hsu, Jyh-Ping, Kao, Chen-Yuan
• Format: Article
• Language: English
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp0209087

The boundary effect on the electrophoresis of an entity is of both fundamental and practical significance. Typical examples include the electrophoresis in a narrow space such as a pore and that of a concentrated dispersion. In this study, the boundary effect on the electrophoretic behavior of a particle is investigated theoretically by considering a finite, charged, cylindrical particle in an uncharged cylindrical pore for the case of low electrical potential. We show that while the direction of the movement of a particle is determined by the charged conditions on its lateral surface, the magnitude of its mobility is mainly controlled by that of the top and bottom surfaces of the particle. It is interesting to note that the mobility of a uniformly charged particle may have a local maximum as the ratio (particle radius/pore radius) varies. The mobility decreases with the increase in the aspect ratio (particle radius/particle length) of the particle. The effect of the presence of the pore on the electrophoretic mobility of the particle increases significantly as the charge density on particle surface increases.