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arXiv · 0809.4083

Optically induced electrokinetic patterning and manipulation of particles

Stuart J. Williams·Aloke Kumar·Steven T. Wereley
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Abstract

This fluid dynamics video showcases how optically induced electrokinetic forces can be used to drive three-dimensional micro-vortices. The strong microfluidic vortices are used constructively in conjunction with other electrokinetic forces to dynamically and rapidly aggregate particle groups. Particle manipulation is achieved on the surface of a parallel-plate gold/indium tin oxide (ITO) electrode that is illuminated with near-infrared (1064 nm) optical patterns and biased with a low frequency ($<$ 100 kHz) alternating current (AC) signal. The fluid dynamics video shows how electrokinetically driven flows in the microdomain can be used for non-invasive particle manipulation.

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Stuart J. Williams, Aloke Kumar, Steven T. Wereley. 2008-10-09. Optically induced electrokinetic patterning and manipulation of particles. https://doi.org/10.1063/1.3200938

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