Reusable molecularly imprinted electrochemiluminescence assay for kanamycin based on ordered mesoporous carbon loaded...

A highly sensitive kanamycin electrochemiluminescence (ECL) switch sensor was constructed. A signal element consisting of ordered mesoporous carbon loaded with indium oxide nanoparticles/carbon quantum dots (OMC/In₂O₃/C-dots) was assembled on the surface of a gold electrode. Then, a molecularly imprinted polymer (MIP) was prepared on the modified electrode surface using kanamycin as the template molecule and o-aminophenol as the functional monomer. After kanamycin elution, the prepared sensor retained specific kanamycin recognition sites. OMC/In₂O₃ effectively amplified the ECL signal of the C-dots, thereby enhancing the detection sensitivity, whereas kanamycin quenched the signal. Therefore, the imprinted sites acted as a switch, providing a new method for detecting kanamycin. Under the optimal experimental conditions, the concentration of kanamycin was proportional to the degree of ECL quenching within a linear range of 5-4500 × 10^-12 mol L^-1 at 0.8 V (vs. Ag/AgCl electrode electrode), and the detection limit was 5.8 × 10^-13 mol L^-1. When applied to the detection of kanamycin in actual samples, such as chicken, duck, pork, and milk, the recovery for spiked samples was in the range 92.7-110%.