Sensitive lead detection through integration of electrochemical deposition and graphene ion-sensitive field-effect transistor

A highly sensitive lead ion sensor is developed using graphene ion-sensitive field-effect transistors (G-ISFETs) in an aqueous environmental setting. The sensing channel employs monolayer graphene, while a PVC membrane, incorporating a lead ionophore, serves as the ion-sensitive membrane. The sensor utilizes an electrochemical deposition technique to preconcentrate Pb ion concentration at the solution-sensor interface to enable detection at ultra-low concentration. Notably, the integrated sensor exhibits an exceptional sensitivity of -36.7 mV/decade and achieves an ultra-low detection limit of 5.6x10(-4) ppt, with a limit of quantitation (LOQ) set at 1.0x10(-3) ppt.