Photoelectrochemical Solution Gated Graphene Field‐Effect Transistor Functionalized by Enzymatic Cascade Reaction for Organophosphate Detection

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2024-11, Vol.20 (44), p.e2402655-n/a
• Main Authors: Wang, Hai‐Rui, Hou, En‐Hui, Xu, Na, Zhang, Yu‐Feng, Wu, Jian‐Feng, Yuan, Wei‐Jian, Kong, Zhi‐Guo, Nie, Ping, Chang, Li‐Min, Zhang, Xue‐Lin, Xie, Jian‐Wei
• Format: Article
• Language: English
• Subjects: Cascade chemical reactions; Electric potential; Electrodes; enzymatic cascade reaction; Graphene; nanomimetic enzymes; Oligomers; Organophosphates; Phenylenediamine; photoelectrochemical solution gated graphene field‐effect transistors; photoelectrochemical transistors; Thickness; Transistors; Voltage
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.202402655

Solution Gated Graphene Field‐Effect Transistors (SGGT) are eagerly anticipated as an amplification platform for fabricating advanced ultra‐sensitive sensors, allowing significant modulation of the drain current with minimal gate voltage. However, few studies have focused on light‐matter interplay gating control for SGGT. Herein, this challenge is addressed by creating an innovative photoelectrochemical solution‐gated graphene field‐effect transistor (PEC‐SGGT) functionalized with enzyme cascade reactions (ECR) for Organophosphorus (OPs) detection. The ECR system, consisting of acetylcholinesterase (AChE) and CuBTC nanomimetic enzymes, selectively recognizes OPs and forms o‐phenylenediamine (oPD) oligomers sediment on the PEC electrode, with layer thickness related to the OPs concentration, demonstrating time‐integrated amplification. Under light stimulation, the additional photovoltage generated on the PEC gate electrode is influenced by the oPD oligomers sediment layer, creating a differentiated voltage distribution along the gate path. PEC‐SGGT, inherently equipped with built‐in amplification circuits, sensitively captures gate voltage changes and delivers output with an impressive thousandfold current gain. The seamless integration of these three amplification modes in this advanced sensor allows a good linear range and highly sensitive detection of OPs, with a detection limit as low as 0.05 pm. This work provides a proof‐of‐concept for the feasibility of light‐assisted functionalized gate‐controlled PEC‐SGGT for small molecule detection. Herein, photoelectrochemical (PEC) as an innovative gating module for solution‐gated graphene field‐effect transistor (SGGT) is realized for the first time by integrating a PEC‐SGGT device. By functionalizing with enzyme cascade reactions comprising acetylcholinesterase (AChE) and CuBTC nanomimetic enzymes, the PEC‐SGGT device achieves excellent analytical performance for organophosphorus (OPs) with a detection limit of 0.05 pm.