Gold nanosheet modified electrode with reduced impedance for electrophysiological recordings

Abstract

In neurophysiological recording, reducing electrode impedance is crucial for enhancing the signal-to-noise ratio and achieving the desired spatial resolution. This study presents an approach to improve the performance of Au/Cr/glass electrodes by incorporating synthesized gold nanosheets without the need for additional adhesive material. We characterized the performance of the modified electrodes using electrochemical impedance spectroscopy and equivalent circuit analysis. Our findings showed an 81% reduction in mean impedance for the modified electrode, which was 0.85 kΩ at 1 kHz, compared to the unmodified electrode at 4.5 kΩ, an improvement attributed to the higher effective surface area of the modified electrode. Additionally, Scanning electron microscopy observations of PC12 cells cultured on the modified electrodes indicated favorable cell elongation and interaction with the rough surface. Stability studies indicated acceptable performance of the modified electrodes in solution environments. These results suggest that surface modification of electrodes with gold nanosheets could be a promising strategy for enhancing neural interface applications.