Ultrafast High-pressure AC Electro-osmotic Pumps for Portable Biomedical Microfluidics

Abstract

This paper details the development of an integrated AC electro-osmotic (ACEO) microfluidic pump for dilute electrolytes consisting of a long serpentine microchannel lined with three dimensional (3D) stepped electrode arrays. Using low AC voltage (1 V rms, 1 kHz), power (5 mW) and current (4.5 mA) in water, the pump is capable of generating a 1.3 kPa head pressure, a 100-fold increase over prior ACEO pumps, and a 1.3 mm/s effective slip velocity over the electrodes without flow reversal. The integrated ACEO pump can utilize low ionic strength solutions such as distilled water as the working solution to pump physiological strength (100 mM) biological solutions in separate microfluidic devices, with potential applications in portable or implantable biomedical microfluidic devices. As a proof-of-concept experiment, the use of the ACEO pumps for DNA hybridization in a microfluidic microarray is demonstrated.