Characterization and Modeling of a Micro-Fluidic Dielectrophoresis Filter for Biological Species,” submitted to J. Microelectromechanical Sys

Abstract—Microfabricated interdigitated electrode array is a convenient form of electrode geometry for dielectrophoretic trap-ping of particles and biological entities such as cells and bacteria within microfluidic biochips. We present experimental results and finite element modeling of the holding forces for both positive and negative dielectrophoretic traps on microfabricated interdigitated electrodes within a microfluidic biochip fabricated in silicon with a 12- m-deep chamber. Anodic bonding was used to close the channels with a glass cover. An Experimental protocol was then used to measure the voltages necessary to capture different particles (polystyrene beads, yeast cells, spores and bacteria) against destabilizing fluid flows at a given frequency. The exper-imental results and those from modeling are found to be in close agreement, validating our ability to model the dielectrophoretic filter for bacteria, spores, yeast cells, and polystyrene beads. This knowledge can be very useful in designing and operating a dielec-trophoretic barrier or filter to sort and select particles entering the microfluidic devices for further analysis. [1181] Index Terms—Dielectrophoretic filter, interdigitated electrode, microfluidic biochip. I