An advanced molecularly imprinted electrochemical sensor based bifunctional monomers for highly sensitive detection of nitrofurazone

The combination of molecularly imprinted technology and electrochemical sensor can prepare stable and excellent anti-interference molecularly imprinted electrochemical sensor (MIECS), realizing the highly specific recognition of nitrofurazone (NFZ). Bifunctional monomers and zeolitic imidazolate frameworks (ZIF) modified carboxylic multi-walled carbon nanotubes (c-MWCNTs) nanocompostites were used to solve the problems of low conductivity and limited number of imprinted holes in molecularly imprinted polymer (MIP) membrane. The porous nanocomposite can efficiently improve the conductivity and increase the surface of electrode, providing abundant molecularly imprinted holes and enabling a wide detection range. Nicotinamide (NA) and 2-amino-5-mercapto-1,3,4-thiadiazole (AMT) acted as bifunctional monomers and NFZ as template molecules, which were electropolymerized to MIP on the modified electrode. In the optimal experimental environment, the electrochemical response of MIECS to NFZ was linear in a certain concentration range. The linear range was from 10–13 M to 10–6 M, and the detection limit was 6.7 ×10–14 M. The MIECS showed excellent anti-interference performance, which was attributed to the unique holes generated by the polymerization of bifunctional monomers. MIECS also owned good stability and reproducibility and has been successfully applied to the detection of actual urine and water samples.