Vitamin C-reduced graphene oxide improves the performance and stability of multimodal neural microelectrodes

Nanocarbons are often employed as coatings for neural electrodes to enhance surface area. However, processing and integrating them into microfabrication flows requires complex and harmful chemical and heating conditions. This article presents a safe, scalable, cost-effective method to produce reduced graphene oxide (rGO) coatings using vitamin C (VC) as the reducing agent. We spray coat GO + VC mixtures onto target substrates, and then heat samples for 15 min at 150 degrees C. The resulting rGO films have conductivities of similar to 44 S cm(-1), and are easily integrated into an ad hoc microfabrication flow. The rGO/Au microelectrodes show similar to 8x ower impedance and similar to 400x higher capacitance than bare Au, resulting in significantly enhanced charge storage and injection capacity. We subsequently use rGO/Au arrays to detect dopamine in vitro, and to map cortical activity intraoperatively over rat whisker barrel cortex, demonstrating that conductive VC-rGO coatings improve the performance and stability of multimodal microelectrodes for different applications.

Automated summary

Using vitamin C as the reducing agent, a cost-effective method to produce reduced graphene oxide coatings has been developed, significantly improving the performance and stability of multimodal microelectrodes.