Fabrication of surface molecularly imprinted electrochemical sensor based on V2CTx MXene heterogeneous functionalized Au-PtRu nanoalloy for the sensitive detection of chlortetracycline in food

A novel molecularly imprinted electrochemical sensor (MIECS) is successfully prepared for the chlortetracycline (CTC) determination in food, based on a gold‑platinum ruthenium/vanadium carbide (Au-PtRu/V 2 CT x ) nanocomposite integrated with a molecularly imprinted polymer (MIP) film. The incorporated nanocomposite, featuring excellent electron transport properties, enhances the current response owing to the synergistic effect between the Au-PtRu nanoalloy (NA) and V 2 CT x MXene. Following a one-step electropolymerization process and the efficient removal of template molecules, imprinted cavities are formed on the imprinted electrode (MIP/Au-PtRu/V 2 CT x /GCE) surface, enhancing the targeted recognition of CTC molecules. Under optimized conditions, the sensor exhibits a broad linear range from 1 to 120 μM with a low detection limit of 0.16 μM (S/N = 3). Besides, the sensor demonstrates excellent selectivity, reproducibility, reusability and stability. Its practical applicability is further validated through CTC detection in food samples, yielding satisfactory spiked recoveries (83.3–93.6 %), which are consistent with high-performance liquid chromatography (HPLC) results.