Sensitive Detection of Umami Substances in Meat with Synthesized Electrochemical Sensor Enhanced by MXene Surface-Doped Peroxidase-Mimic Nanoenzymes (Fe3O4)

Electrochemical analysis is a powerful analytical technique with extensive applications in the food industry, offers high advantages due to its high sensitivity, low operating cost, and high-speed analysis. In this study, a novel nanoenzymes high-catalytic platform based on a conductive polymer (MXene) was established for the detection of Guanosine 5 '-monophosphate (GMP). The MXene/Fe3O4/beta-CD nanocomposites were synthesized using a self-assembly method, exhibiting significant catalytic activity and a large specific surface area. The surface morphology, functional groups and chemical bonds of MXene/Fe3O4/beta-CD were analyzed via scanning electron microscopy (SEM), Fourier Transform Infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS). Electrochemical experiments indicated a significant amplification of GMP electrical signals on the nanoenzymatic platform. The oxidation of GMP to 8-oxo-GMP involved the transfer of two electrons (-2e(-)) and two protons (-2H(+)) at the MXene/Fe3O4/beta-CD modified glassy carbon electrode. Under optimized conditions, this electrochemical nanoenzymatic platform achieved a low detection limit of 0.0126 mu M for GMP, with linear ranges from 0.05 mu M to 600 mu M. The sensor demonstrated excellent selectivity and stability and was successfully applied for GMP determination in chicken, fish, pork and beef samples. This study provided a new pathway for the development of sensors for GMP detection.