A Low-Cost Multi-Electrode Array System for the Simultaneous Acquisition of Electrophysiological Signal and Cellular Morphology

This study aimed to develop a low-cost multichannel neural recording system and multi-electrode array (MEA) chip for a number of research laboratories. Because these elaborate systems may be cost-prohibitive for many laboratories, the simple fabrication of the MEA chip and the construction of the low-cost recording system with cellular image acquisition is presented in this study. The MEA chip is a polyimide-based microelectrode array with 60 electrodes (5 μm thick, 30 μm in radius and with 200 μm spacing) and is based on the semiconductor process and advanced microelectro-mechanical system (MEMS) technology. The three-dimensional (3D) structure of the electrodes is fabricated by electroplating, which produces rough textures that increased the effective surface area. The in vitro impedance of the electrodes on the MEA chip is 0.43±0.024 MΩ at 1 kHz, which is sufficiently low for obtaining high-quality neural recordings. A self-built amplifier (79 dB) and filter (100 Hz∼5 kHz) were implemented for signal conditioning. Furthermore, with the help of the National Instruments system and LabVIEW graphic interface, multichannel neural signals and cellular images can be simultaneously acquired using this low-cost neural recording system. With good biocompatibility, a high and stable SNR for neural recording, and a high tolerance for chemical and electrolytic erosion, the laboratory-designed MEA-based recording can serve as a useful device in neuroscience research