Construction of electrochemical immunosensors based on Au@MXene and Au@CuS nanocomposites for sensitive detection of carcinoembryonic antigen.

Cancer is currently one of the major causes of human mortality and has received widespread attention. In this paper, Au@CuS composite nanomaterial as a sandwich immunosensor tag for carcinoembryonic antigen (CEA) detection strategy was studied. Herein, Au@CuS composite nanomaterials were obtained by Au nanoparticles modified with CuS, which were combined with secondary antibody (Ab) to construct an immunosensor that interacted with HO to produce a current response. The anti-CEA primary antibody (Ab) was fixed on the glassy carbon electrode (GCE) modified by Au@MXene. The completed electrochemical immunosensor was constructed with rapid detection and high sensitivity for CEA. Under optimal conditions, the linearity ranged from 0.01 pg/mL to 0.5 ng/mL, and the detection limit was 3.8 fg/mL. This tactic possesses good reproducibility, constancy and selectivity. At the same time, this strategy has latent practical value for the test of other tumor markers.