Microfluidic Electrical Impedance Spectroscopy

Abstract

The goal of this study is to design and manufacture a microfluidic device capable of measuring changes in impedance valuesof microfluidic cell cultures. Tocharacterize this, an interdigitated array of electrodes was patterned over glass, where it was then bonded to a series of fluidic networks created in PDMS via soft lithography. The device measured ethanol impedance initially to show that values remain consistent over time. Impedance values of water and 1% wt. saltwater were compared to show that the device is able to detect changes in impedance, with up to a 60% reduction in electrical impedance in saltwater. Cells were introduced into the device, where changes in impedance were seen across multiple frequencies, indicating that the device is capable of detecting the presence of biologic elements within a system. Cell measurements were performed using NIH-3T3 fibroblasts.