Related Experiment Video
Updated: Jun 10, 2026

Label-free Isolation and Enrichment of Cells Through Contactless Dielectrophoresis
Published on: September 3, 2013
Application of capillary electrophoresis to predict crossover frequency of polystyrene particles in dielectrophoresis
Christian M White1, Lisa A Holland, Parviz Famouri
1C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV, USA.
Abstract:
CE is used to calculate the zeta potential of polystyrene particles in order to estimate the surface conductivity of the particles. These values are used to predict the dielectrophoretic behavior, including the crossover frequency of particles under the influence of an AC electric field. Predictions for fluorescent polystyrene particles that are unmodified, carboxylate-modified, or streptavidin-modified are tested using miniaturized dielectrophoresis cells containing patterned gold quadrupole electrodes. The particle surface conductivities derived from CE separations differ from those derived from dielectrophoresis experiments by < or =0.003 S/m and serve as a guide to effectively select the suspending medium to generate a crossover frequency approximately 0.5 MHz. Prediction of dielectrophoresis crossover frequency is limited by several factors, especially the accuracy and precision of the conductivity measurements for the particle and suspending medium. A rapid analysis of particles by CE is a viable alternative to determine zeta potential.
Related Concept Videos
Capillary Electrophoresis: Applications
Capillary zone electrophoresis (CZE) separates ionic components based on their electrophoretic mobility. It has been used to separate proteins, amino acids,...
Electrophoresis: Overview
There...
Capillary Electrophoresis: Instrumentation
Two-dimensional Gel Electrophoresis
The first dimension separation uses the isoelectric focusing or IEF technique performed on immobilized pH gradient (IPG) strips that separate proteins according to their isoelectric points.
Biological samples, such as cells...
SDS-PAGE
A variation of gel electrophoresis, termed polyacrylamide gel electrophoresis (PAGE), is commonly used for separating proteins according to their molecular size by passing them through a polyacrylamide gel. Because of the varying charges associated with amino acid side chains, PAGE can be used to separate intact proteins...
Dielectric Polarization in a Capacitor

