Electrochemical sensor using neomycin-imprinted film as recognition element based on chitosan-silver nanoparticles/graphene-multiwalled carbon nanotubes composites modified electrode

A novel imprinted electrochemical sensor for neomycin recognition was developed based on chitosan-silver nanoparticles (CS-SNP)/graphene-multiwalled carbon nanotubes (GR-MWCNTs) composites decorated gold electrode. Molecularly imprinted polymers (MIPs) were synthesized by electropolymerization using neomycin as the template, and pyrrole as the monomer. The mechanism of the fabrication process and a number of factors affecting the activity of the imprinted sensor have been discussed and optimized. The characterization of imprinted sensor has been carried out by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The performance of the proposed imprinted sensor has been investigated using cyclic voltammetry (CV) and amperometry. Under the optimized conditions, the linear range of the sensor was from 9×10−9 mol/L to 7×10−6 mol/L, with the limit of detection (LOD) of 7.63×10−9 mol/L (S/N=3). The film exhibited high binding affinity and selectivity towards the template neomycin, as well as good reproducibility and stability. Furthermore, the proposed sensor was applied to determine the neomycin in milk and honey samples based on its good reproducibility and stability, and the acceptable recovery implied its feasibility for practical application.

► A selective electrochemical molecularly imprinted sensor for the detection of neomycin was developed.
► CS-SNP and GR-MWCNTs nanocomposites were used to improve the sensitivity of the sensor.
► MIPs were synthesized by electropolymerization using neomycin as the template, and pyrrole as the monomer.
► The sensor showed high selectivity, excellent stability and good reproducibility for the determination of neomycin.
► The developed sensor was successfully used for neomycin determination in real spiked samples.