Dual-Gate Organic Electrochemical Transistors Based on Laser-Scribed Graphene for Detecting Dopamine and Glutamate

Organic electrochemical transistors (OECTs) are gaining significant attention due to their high sensitivity, customizability, ease of integration, and low-cost manufacturing. In this paper, we design and develop a flexible dual-gate OECT based on laser-scribed graphene (LSG) with modified OECT gates for the detection of dopamine and glutamate, two critical neurotransmitters (NTs). The developed OECTs are fully carbon-based and environmentally friendly. By modifying the gates of OECTs with biopolymer chitosan and L-Glutamate oxidase enzyme, highly selective and sensitive measurements are successfully achieved with detection limits of 5 nm for dopamine and 1 µm for glutamate, respectively. The modified dual-gate shows no interference between the detections of two neurotransmitters, making it a promising tool for customized multi-neurotransmitter analysis. The results demonstrate the potential of LSG-based OECTs in customizable biosensing applications, offering a flexible, cost-effective platform for biomedical disorder diagnostics.