Electrolyte-Gated Organic Field Effect Transistor Integrated in Neurosignal Recording System for Monitoring Brain Activity

Electrolyte-gated organic field-effect transistors (EGOFETs) have emerged as promising candidates for neurosignal detection, due to their high operating speed, effective transduction of biological inputs into amplified transistor signals and ability to operate stably in aqueous environments. Key limitations in these current microelectrode neuroprobes stemming from high electrode impedance and voltage drift, have necessitated innovative neurosignal recording solutions. In this study, we present a neural recording system that utilizes EGOFETs for on-site signal amplification. We demonstrate the capability of EGOFETs, when integrated into our recording circuit, to record neurosignals with an exceptional signal-to-noise ratio (SNR) at 16 dB and high fidelity. These EGOFETs are based on top liquid gate and top contact configuration, which can operate under low source-drain voltage (<i>V</i>_DS = -1.2 V) and gate voltage (<i>V</i>_G = 0 V) conditions, achieving a remarkable maximum transconductance of up to 500 μS. This achievement underscores the potential for broad applications of EGOFET technology in monitoring brain activity, encompassing both research and clinical domains.