Controlled Electrodeposition of Graphene Oxide Doped Conductive Polymer on Microelectrodes for Low-Noise Optogenetics

The optrode integrated with light sources and electrical recording electrodes presents significant advantages. However, the performance of the optrode is still hindered by photoelectric artifact generated by optical stimulation. A controlled electrodeposition method of PtBlack/PEDOT-GO (graphene oxide doped poly(3,4-ethylenedioxythiophene)) double layer on gold microelectrode is developed for noise reduction in this work. The microscopic characterization shows that Pt-Black can increase the adhesion of PEDOT-GO to the substrate and prevent it from spreading around, thereby avoiding short circuits in adjacent microelectrodes. Moreover, the electrochemical measurements show that Pt-Black/PEDOT-GO can decrease impedance and improve electrochemical performance dramatically. Finally, the bench noise recordings show that PtBlack/PEDOT-GO can simultaneously reduce background noise, photovoltaic noise and photoelectrochemical noise to less than 100 μV.