A sensitive enzyme-free electrochemical sensor based on ZnWO4/γ-Fe2O3 magnetic molecularly imprinted polymer for specific recognition and determination of Chloramphenicol

A chloramphenicol (CAP) electrochemical sensor based on zinc tungstate and magnetic hematite (ZnWO 4 /γ-Fe 2 O 3 ) magnetic molecularly imprinted polymer (ZnWO 4 /γ-Fe 2 O 3 /MIP) is proposed. First, ZnWO 4 , γ-Fe 2 O 3 nanomaterials were synthesized by one-step hydrothermal method, and then ZnWO 4 , magnetic nanoparticles were combined with molecularly imprinted polymers, that is, ZnWO 4 /γ-Fe 2 O 3 was coated with a molecularly imprinted (MIP) shells by precipitation polymerization method to prepare magnetic molecularly imprinted nanomaterials, and then modified on glassy carbon electrodes to construct an electrochemical sensor for the determining of CAP. The results show that under the optimal conditions, the ZnWO 4 /γ-Fe 2 O 3 /MIP (MMIP) modified electrode has a stronger CAP detection reduction peak current than the one-component electrode, and exhibits better electrocatalytic activity, which is an excellent electrochemically modified electrode. Compared to magnetic non-molecular imprint sensors (MNIP), MMIP sensors have higher detection efficiency. The linear range of ZnWO 4 /γ-Fe 2 O 3 /MIP/GCE for the detection of CAP was 0.12 ∼ 1224 μM, and the detection limit was 0.034 μM, showing excellent stability and reproducibility, and good selectivity in the presence of different interferences. ZnWO 4 /γ-Fe 2 O 3 /MIP/GCE was applied to the detection of CAP in milk samples with satisfactory results.