Graphene microelectrode arrays for neural activity detection

• Published in: Journal of biological physics Vol. 41; no. 4; pp. 339 - 347
• Main Authors: Du, Xiaowei, Wu, Lei, Cheng, Ji, Huang, Shanluo, Cai, Qi, Jin, Qinghui, Zhao, Jianlong
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.09.2015; Springer Nature B.V
• Subjects: Action Potentials; Animals; Biochemistry; Biocompatibility; Biological and Medical Physics; Biophysics; Complex Fluids and Microfluidics; Complex Systems; Electric Impedance; Electrodes; Electrophysiology - instrumentation; Gold - chemistry; Graphite - chemistry; Microelectrodes; Neurons - cytology; Neurosciences; Original Paper; Physics; Physics and Astronomy; Rats; Rats, Wistar; Soft and Granular Matter; Studies; MEA; Neural activity detection; Graphene; Microelectrode arrays
• ISSN: 0092-0606; 1573-0689
• DOI: 10.1007/s10867-015-9382-3

We demonstrate a method to fabricate graphene microelectrode arrays (MEAs) using a simple and inexpensive method to solve the problem of opaque electrode positions in traditional MEAs, while keeping good biocompatibility. To study the interface differences between graphene–electrolyte and gold–electrolyte, graphene and gold electrodes with a large area were fabricated. According to the simulation results of electrochemical impedances, the gold–electrolyte interface can be described as a classical double-layer structure, while the graphene–electrolyte interface can be explained by a modified double-layer theory. Furthermore, using graphene MEAs, we detected the neural activities of neurons dissociated from Wistar rats (embryonic day 18). The signal-to-noise ratio of the detected signal was 10.31 ± 1.2, which is comparable to those of MEAs made with other materials. The long-term stability of the MEAs is demonstrated by comparing differences in Bode diagrams taken before and after cell culturing.