ABSTRACT
Most substances acquire a surface electric charge when brought into contact with a polar, normally aqueous medium. The underlying charging mechanisms, leading to the forma tion of an electrical double layer, are dissociation, ion adsorption, and ion dissolution. One of the electrokinetic phenomena which arises when attempts are made to shear off the mobile part of the electrical double layer from a charged surface is the movement of a charged particle surface relative to stationary liquid by an applied electric field (particle electrophoresis). The mobility of a particle under the influence of an electric field appears to depend entirely on the nature of the particle surface, and is independent of the size or the nature of the particle itself. Reuss may be considered to have provided the first demonstration of electrophoretic phenomena in 1809 [1]
Particle electrophoresis has an important practical applicability for the characteriza tion and control of the surface behavior of particles in fields such as colloid and polymer chemistry, biotechnology, and biological applications. Thus, considerable efforts have been undertaken to develop and improve this surface characterization technique. A remarkable advance in particle electrophoresis was the electrophoretic fingerprinting introduced by Marlow and coworkers [2-16]. The electrophoretic mobility has been shown to be a function of the measurable quantities pH and specific conductance of the medium [17, 18]. Thus, the electrophoretic fingerprint is a three-dimensional diagram of these experimental data which can be used to characterize an unknown system of particles or to explore the nature of the electrochemical surface.
