Covalent molecularly imprinted electrochemical sensor modulated by borate ester bonds for hygromycin B detection based on the synergistic signal amplification of Cu-MOF and MXene.

A molecularly imprinted electrochemical sensor (MIES) modified with Cu-MOF and Ti3C2Tx was successfully prepared for the detection of hygromycin B in food. According to the pH sensitive property of reversible borate ester bonds, a molecularly imprinted polymers (MIP) were constructed on the modified gold electrode (GE) surface by electropolymerization to realize the controllable elution and adsorption of template molecules. Cu-MOF with large specific surface area and Ti3C2Tx with excellent electrical conductivity cooperate to improve the overall analytical performance of MIES. The morphology and electrochemical performance of the sensor were evaluated. Under the optimal experimental conditions, the method showed superior selectivity to hygromycin B with a linear range of 5 × 10-9-5 × 10-6 M and a detection limit of 1.92 × 10-9 M (S/N = 3). The detection results of this method are in good agreement with HPLC-MS/MS, which proves that the method has reliable practicability and accuracy.