Compact Micro-Stereolithographic (µSLA) Printed, 3D Microelectrode Arrays (3D MEAS) with Monolithically Defined Positive and Negative Relief Features For in Vitro Cardiac Beat Sensing

We demonstrate a novel microfabrication and assembly strategy for the realization of 3D Microelectrode Arrays (3D MEAs) in compact form-factors. An optimized Micro-Stereolithographic (µSLA) 3D printing process was utilized to ensure complete definition of both positive and negative relief features. Electrical contacts (traces, pads, and electrodes) were established with thin-film metallization through a shadow mask and double-side processing, and the functional Insulation material and subsequent culturing area was defined utilizing a biolaminate layer. In this work, we present the results of this fabrication, impedance spectroscopy, root mean square (RMS) noise characterization, laser confocal analysis of the defined vias, along with optical and SEM imaging of the platform and electrophysiological spike data from a confluent HL-1 cardiac cell culture at 7 DIV (days in vitro).