Application of Planar Microelectrode Array Modified by Nano-structure Titanium Nitride on Dual Mode Neural Information Recording

The nano-structure TiN was modified on the laboratory self-made planar microelectrode array pMEA by magnetron sputtering method. The performance of modified pMEA was investigated. The research on neuroelectrical and neurochemical recording was studied in vitro. The impedance of the modified pMEA was decreased almost one order of magnitude, and the background noise level was reduced to ±6 μV. In the same testing environment, the signal-to-noise ratio (SNR) of modified electrodes was 1.7 times of bare electrodes. The SNR of neuroelectrical recording on the brain slice of SD rats reached 10:1, and the weak signal such as ±12 μV was separated easily. For neuroelectrical recordings, the detection limit of dopamine (DA) solution reached 50 nM with the 2:1 SNR. In the concentration range of 0.05–100 μM, the linearly dependent coefficient of the DA oxidation currents was 0.998. The modification of nano-structure TiN on pMEA reduced pMEA impedance and background noise level, meanwhile the SNR was increased. The weak signals of neuroelectrical and neurochemical recording were successfully recorded.