AC electrothermal micropump for biofluidic applications using numerous microelectrode pairs

Abstract

Electrokinetic phenomena are widely studied techniques used for micro-scale fluid delivery in many microfluidic application areas such as drug delivery, lab-on-a-chip, and biochemical analysis. AC electrothermal (ACET) micropumps are capable of operating at low voltages (up to 10 V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rms</sub> ) and are suitable for applications involving high conductivity fluids (higher than 0.1 S/m), such as biological fluids. Electrothermal flow is induced by temperature gradients in the presence of a non-uniform electric field. ACET micropumps reported to date have low flow rates (up to 100nl/s) and relatively low back-pressures (up to 1kPa), limiting their utility. In addition, ACET arrays reported in the literature typically feature only a few electrode pairs. In this paper a long fluidic micro-channel, featuring an ACET micropump consisting of a row of 64 asymmetric coplanar microelectrodes is studied in order to investigate the effect of the number of microelectrode pairs on fluid flow. A simulation study is also performed for different numbers of microelectrode pairs. The results show that increasing the number of microelectrode pairs is an efficient way for increasing fluid flow of high conductivity fluids using ACET.