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Micromixer utilizing electrokinetic instability-induced shedding effect.

Chang-Hsien Tai·Ruey-Jen Yang·Min-Zhong Huang·Chia-Wei Liu·Chien-Hsiung Tsai·Lung-Ming Fu
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Abstract

This paper presents a T-shaped micromixer featuring 45 degrees parallelogram barriers (PBs) within the mixing channel. The presented device obtains a rapid mixing of two sample fluids with conductivity ratio of 10:1 (sample concentration:running buffer concentration) by means of the electrokinetic instability-induced shedding effects which are produced when a direct current (DC) electric field of an appropriate intensity is applied. The presented device uses a single high-voltage power source to simultaneously drive and mix the sample fluids. The effectiveness of the mixer is characterized experimentally as a function of the applied electrical field intensity and the extent to which the PBs obstruct the mixing channel. The experimental results indicate that the mixing performance reaches 91% at a cross-section located 2.3 mm downstream of the T-junction when the barriers obstruct 4/5 of the channel width and an electrical field of 300 V/cm is applied. The micromixing method presented in this study provides a simple low-cost solution to mixing problems in lab-on-a-chip systems.

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Equipment DesignMicrofluidic Analytical TechniquesJournal ArticleResearch Support, Non-U.S. Gov't

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Chang-Hsien Tai, Ruey-Jen Yang, Min-Zhong Huang, Chia-Wei Liu, Chien-Hsiung Tsai, Lung-Ming Fu. 2006. Micromixer utilizing electrokinetic instability-induced shedding effect.. https://doi.org/10.1002/elps.200500900

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