Biomimetic imprinted electrochemical sensor for selective detection of streptomycin residue in milk

A novel imprinted electrochemical sensor for streptomycin recognition was developed by using the electrodes decorated with graphene oxide (GO) and chitosan (CS) composites. Molecularly imprinted polymer (MIP) was synthesized by electropolymerization with streptomycin (STR) as the template, and 3-aminophenylboronic acid (APBA) and aniline (AN) as the monomers. The fabrication procedure was studied and optimized along with a number of affecting factors. Scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FTIR) were used to analyze the imprinted sensor. Electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV), and cyclic voltammetry (CV) were used to evaluate the recognition performance of the sensor. Under the optimized conditions, a linear range of the sensor from 2.0×10-10 mol/L to 1.0×10-6 mol/L was calculated with the detection limit of (LOD) 2.54×10-13 mol/L. High binding affinity and selectivity for the template STR were displayed by the molecular imprinted sensing interface. The proposed sensor was successfully used to rapidly and accurately detect STR in milk samples with recoveries from 89.46% to 101.2%. It also demonstrated satisfactory repeatability, stability and regeneration capacity. This study not only serves as a valuable reference for other related research, but also has great significance for food safety inspection.