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arXiv · 0705.1156

A soft-lithographed chaotic electrokinetic micromixer for efficient chemical reactions in lab-on-chips

M. Campisi·D. Accoto·F. Damiani·P. Dario
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Abstract

Mixing is one of the basic functions which automated lab-on-chips require for the effective management of liquid samples. In this paper we report on the working principle, design, fabrication and experimental characterization of a soft-lithographed micromixer for microfluidic applications. The device effectively mixes two liquids by means of chaotic advection obtained as an implementation of a Linked Twisted Map (LTM). In this sense it is chaotic. The liquids are electrokinetically displaced by generating rolls through AC electroosmosis on co-planar electrodes. The device performance has been tested on dyed DI-water for several voltages, frequencies and flow-rates, displaying good mixing properties in the range of $10 \div 100$kHz, at low peak-to-peak voltages ($\sim15 \div 20$ volts). Low voltage supply, small dimensions and possibility of fabrication via standard lithographic techniques make the device highly integrable in lab-on-a-chip platforms.

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M. Campisi, D. Accoto, F. Damiani, P. Dario. 2007-05-08. A soft-lithographed chaotic electrokinetic micromixer for efficient chemical reactions in lab-on-chips. https://doi.org/10.1007/s12213-010-0024-3

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