An electrochemical immunosensor based on MXene–Au and Au–Ce-COF to detect methyl parathion

A novel electrochemical immunosensor based on MXene-Au and Au-Ce-COF was constructed and applied for the ultra-sensitive detection of methyl parathion (PTM). The MXene-Au nanomaterials were obtained by acid etching the precursor to obtain layered MXene, and then generating gold nanoparticles (Au NPs) <i>in situ</i> on the MXene surface. A Au-Ce-COF was synthesized by first synthesizing a Ce-COF through simple stirring under nitrogen (N₂), and then Au NPs were generated by reducing HAuCl₄ (chloroauric acid); finally, the material was ultrasonically synthesized to form the final product. The materials were characterized by multiple techniques with their electrochemical properties evaluated <i>via</i> cyclic voltammetry (CV). Electrochemical test results indicate that the fabricated sensor demonstrates outstanding electrocatalytic performance for PTM detection. In addition, the constructed sensor shows an extended linear response range (0.00475-9.5 μg mL^-1), lower limit of detection (1.58 ng mL^-1), and promising application in practical assays.