Triple-Template Molecularly Imprinted Electrochemical Sensor Based on Ni,Co/NC@CNTs Derived from ZIF-67 for Highly...

The structural and chemical similarities of isomers pose significant challenges for their accurate and simultaneous determination. In this study, for the first time, a novel triple-template molecularly imprinted electrochemical sensor (MIP-ECS) was constructed for the simultaneous, highly sensitive differentiation and detection of three dihydroxybenzene isomers. Benefiting from the porous structure provided by the ZIF derivative, the in situ-grown highly graphitized carbon nanotubes (CNTs) and the highly dispersed bimetallic nanoparticles provide abundant active sites for the electrocatalytic oxidation of isomer molecules and accelerate the charge-transfer rate. Under the optimal experimental conditions, the MIP/Ni,Co/NC@CNTs shows a wide linear range for the simultaneous detection of HQ, CC, and RC (0.2-303 μM for HQ, 0.2-213 μM for CC, and 5-230 μM for RC), with detection limits of 11.81 nM for HQ, 17.47 nM for CC, and 344.2 nM for RC, respectively. Meanwhile, the MIP-ECS also exhibits excellent stability and selectivity and has been successfully applied to the determination of the three isomers in real samples (landfill leachate, textile wastewater, and tap water) with a recovery range of 97.1-103.8%. This work applies ZIF-derived and carbon nanocomposites to multitemplate MIPs, providing a revolutionary method for the specific recognition and simultaneous detection of isomers in the environment.