Impact of open surface area of Multi-Well Microelectrode Array on mammalian brain cells recording efficiency

摘要

Neuro-electrophysiology allows scientists to investigate the underlying electrical properties that constitute brain neuralnetwork assembly. Developing tools to study these properties is a rapidly-evolving research field, and recentadvancements in micro electrode arrays (MEAs) is opening a new frontier in long-term data acquisition. MEAmicrofabrication techniques have advanced over the years and led to different types of electrodes. The objective of thisstudy was to optimize MEA design featuring multiple wells per electrodes (MW-MEA), to improve the recordingefficiency of MEAs used for in vitro electrophysiological recordings. Methods: Two multi-well electrode designs (5wells with diameter of 20 μm vs. 6 wells with diameter of 15 μm) were evaluated. Peak to peak signal amplitude of therecorded signals and the noise levels were studied and the signal to noise ratios (SNR) were determined. Results: Thesignal amplitudes recorded by electrodes with 6 wells (1060.3 μm~2) was higher than those recorded by 5-wells electrodes(1570.8 μm~2), while the noise level remained identical in both designs (31.3 μv ± 10.2). As such, the SNR recorded bythe 6-wells electrodes showed a 1.8-time increase, compared to the electrodes with 5 wells, although the diameter of thewells in the former design was smaller. The results of this study demonstrated an inverse relation between SNR and opensurface area of electrodes. Significance: The identified relation between electrode well characteristics and MW-MEAperformance and design optimization can improve signals’ resolution during long-term spontaneous extracellularrecordings and thus the quality of brain cell activity recordings.