An in-situ fabrication technique to form integrated microelectrodes

Abstract

In this study we have developed a new fabrication method to form microelectrodes for microfluidic applications. We present a microfabrication route to achieve embedded microelectrodes within a microchannel without needing for a microfabrication facility or lithography and metallization processes. This method includes attaching a gold microwires on a glass slide and bonding PDMS micro channels perpendicular to the microwire. Then aqua regia solution is passed through the channel etching the wire inside of the channel and forming two electrodes on the two sides. We applied these electrodes to the impedance flow cytometry for high sensitive detection of polystyrene beads and red blood cells. We also compared the performance of our electrodes with the coplanar electrodes which is the most commonly used geometry of the impedance flow cytometry. The etched electrodes give up to 20 times better SNR compared to coplanar electrodes. © 15CBMS-0001.