Electrokinetic (EK) micromixers have been widely studied in the past decade for biochemical applications

biological and chemical analysis

etc

. Unfortunately

almost all EK mixers require different electrical conductivity between the two fluids to be mixed

which has greatly limited their wide applications

in cases where the two streams to be mixed have equivalent electrical conductivity. Here we show that mixing enhancement between two fluids with identical conductivity can be achieved in an EK micromixer with conductive sidewalls

where the electric field is in transverse direction of the flow. The results revealed that the mixing became stronger with increased conductivity value. This mixing method provides a novel and convenient strategy for mixing two liquids with the same or similar electrical conductivity in microfluidic systems

and could potentially serves as a powerful tool for sample preparation in applications such as liquid biopsy

and environmental monitoring

etc

.