Development of A Bioelectronic Device for In Vitro Electrical Impedance Monitoring Using 3D Printed Conducting Hydrogel Scaffolds

Bioelectronic in vitro devices use electronics integrated with biology to monitor or influence cell behavior, with many methods using impedance to measure cell viability. By incorporating soft, 3-dimensional substrates into bioelectronics, we increase the relevancy of cell behavior by mimicking the in vivo environment. Previously, we have published a method for fabricating soft, tissue-like scaffolds by 3D printing a conducting polymer hydrogel, poly(3,4 - ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). Here, we present a novel method for anchoring these scaffolds into a fabricated device, enabling noninvasive electrical monitoring of cells growing on the scaffolds. The substrate, insulating material, adhesion method, and assembly were all optimized for ease of fabrication, electrical performance, and cytocompatibility. Characterization of the device reveals that the PEDOT:PSS structure reduces impedance and is stable for up to 56 days in solution. Studies in cell culture conditions suggest that the device's impedance will stabilize after multiple days in media. Preliminary cell culture experiments provide proof of concept for the device’s use in drug screening for ovarian cancer. This report presents a customizable 3D cell sensing platform that can noninvasively monitor cell viability with future applications in personalized medicine using patient-derived cells.