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Updated: Mar 26, 2026

Label-free Isolation and Enrichment of Cells Through Contactless Dielectrophoresis
Published on: September 3, 2013
Low-frequency dielectrophoretic response of a single particle in aqueous suspensions
Jingyu Wang1, Ming-Tzo Wei2, H Daniel Ou-Yang
1Department of Physics, Lehigh University , Bethlehem, Pennsylvania 18015, USA.
Abstract:
We use optical tweezers-based dielectrophoresis (DEP) force spectroscopy to investigate the roles of the electrical double layer in the AC dielectric response of an individual colloidal particle in an aqueous medium. Specifically, we measure the DEP crossover frequency as a function of particles size, medium viscosity, and temperature. Experimental results were compared to low frequency relaxation mechanisms predicted by Schwarz, demonstrating the dielectrophoretic responses in the frequency range between 10 kHz and 1 MHz were dominated by counterion diffusion within the electric double layer.
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