Experimental and Modeling Based Investigations of Process Parameters on a Novel, 3D Printed and Self-Insulated 24-Well, High-Throughput 3D Microelectrode Array Device for Biological Applications

We have investigated the effect of printing angle and device orientation on the development of high-throughput (HT), self-insulated, 3D printed 3D Microelectrode Arrays (HT-3DMEAs) for
in vitro
biotechnology applications and its repercussions for optical, mechanical, and electrical properties of the final device. Makerspace based development using micro-Stereolithography (
$\boldsymbol {\mu }$
SLA) 3D printing and ink casting technique were carried out to develop a 24-well device with self-insulated 3D microelectrodes, with
100% yield and 7 microtowers per well
acting as supports for the microelectrodes. These MEAs were further characterized by Optical Microscopy, Electrical Impedance Spectroscopy (EIS), Laser Scanning Confocal Microscopy, Scanning Electron Microscopy (SEM), and UV-Vis Spectroscopy. Surface flatness required for the microelectrode formation was obtained for 0° tilt printed version at top-side orientation. The process optimization and results were interpreted using established
$\boldsymbol {\mu }$
SLA theory and COMSOL modeling. Artifact size determination with a maximum 6% error was predicted. Experimental finding on the microelectrode formation, i.e., a potentially useful microbullet shape was observed and confirmed using Laser Confocal and SEM microscopy characterization and COMSOL simulation. These results allow for greater understanding of the device-process relationships for HT-3DMEAs and paves the pathway towards scalability, denser electrodes and even higher well counts for HT screening in biotechnology. [2021-0201]