(65j) Microbe Removal Using Reservoir-Based Dielectrophoresis (rDEP)

The removal of pathogenic microbes from water is critical to human life. In this talk we present a novel electric field-driven technique for continuous removal of microbes from water in a stacked microfluidic device. This technique, termed reservoir-based dielectrophoresis (rDEP), is based on the dielectrophoretic motion induced at the reservoir-microchannel junction as a result of the inherent size mismatch between the reservoir and the microchannel. In order to increase the throughput, multiple layers of PDMS slabs are stacked and each layer also consists of multiple microchannels. We demonstrate the continuous rDEP trapping and filtration of yeast cells from water in different regions inside the inlet reservoir simultaneously. The effects of electric field (including magnitude, AC to DC field ratio, and frequency) and suspending medium (primarily the electric conductivity) on the filtration performance are studied. A numerical model is also developed to simulate the electrokinetic transport and manipulation of cells in the stacked microfluidic device.