Optically induced electrokinetic patterning and manipulation of particles

TL;DR

This paper demonstrates how optically induced electrokinetic forces can generate micro-vortices to dynamically manipulate particles in microfluidic environments using near-infrared illumination and AC bias.

Contribution

It introduces a novel method combining optical patterns and electrokinetics to achieve rapid, non-invasive particle manipulation in microfluidic systems.

Findings

Generation of 3D micro-vortices via optical electrokinetics

Effective aggregation of particle groups using induced flows

Non-invasive particle manipulation demonstrated

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.