A Signal-On Photoelectrochemical Immunosensor Based On Bi2MoO6 Nanosheets for Carcinoembryonic Antigen Analysis

Herein, a Bi(2)MoO(6 )nanosheet (BMONS)-based sensing platform for signal-on photoelectrochemical (PEC) detection of carcinoembryonic antigen (CEA) is successfully constructed by employing an enzyme-catalyzed reaction as the signal amplification method. Specifically, as the CEA concentration escalates, a substantial accumulation of immunological complexes is triggered by the interaction between antigens and antibodies, which promptly concentrate glucose oxidase (GOD) within the wells of a 96-well microplate. These sequestered GOD molecules subsequently catalyze the hydrolysis of glucose to yield H2O2, an efficient hole scavenger, leading to significant amplification of the PEC response from the photosensitive materials. Under meticulously optimized conditions, a broad linear detection range spanning from 0.05 to 50 ng mL(-1) with a low limit of detection of 0.023 ng mL(-1) is realized for the detection of CEA. This exceptional performance underscores the successful implementation and efficacy of the BMONS-based PEC-sensing platform, which offers promising avenues for sensitive and selective biomarker detection.