A Novel Microelectrode Array Probe Integrated With Electrophysiology Reference Electrode for Neural Recording

摘要

Implantable microelectrode array advanced the study of brain function by simultaneously recording signals from different groups of neurons,gathering spatiotemporal information regarding complex neural processes.In the neural recording experiment there should be an electrophysiology reference electrode implanted in the rat brain,thus the rat would be hurt more and the experiment would be more complex,and all of these might affect the neural signals.This article presents the fabrication,characterization and use in vivo neural recording of an implantable microelectrode array probe which integrated with electrophysiology reference electrode.The probe was implemented on Silicon-On-Insulator (SOI) wafer using Micro-Electro-Mechanical-Systems (MEMS) methods,so the recording-site configurations and high-density electrode placement could be precisely defined.The 16 recording sites and the reference electrode were made of platinum.Double layers of platinum electrodes were used so that the width of the reference electrode was as small as 6 μm.The average impedance of the novel microelectrodes was 0.13 MΩ at 1 kHz.The probe has been employed to record the neural signals of rat,and the results showed that the signal-to-noise ratio (SNR) of the novel probe was 10 and the ordinary probe was 3.For the 16 recording sites,the number of effective recording sites which have recorded useful signals was 9 for the probe with reference electrode and 6 for the ordinary probe.