Abstract:A glass electrode was initially modified by electrodeposition of nanogold and polymerization of polythionine. Then, using salbutamol as a molecular template, a nano-Au/polythionine/salbutamol molecular imprinting electro-biosensor, with specific recognition capability, was prepared by electropolymerization of α-methacrylic acid (MAA) on the surface. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were employed to characterize the different modified electrodes; preparation of the modified electrodes and the detection conditions were optimized, and the selectivity responses of the biosensor towards the template molecule were investigated. The results showed that under the optimum condition, the ratio of molecular template to functional monomer was 1:4; 15 polymerization cycles were carried out, and 0.5 mmol/L sulfuric acid and acetonitrile=1:9 (V/V) was used to elute for 10 min. The DPV measurement was conducted at pH 7.0 in phosphate-buffered saline (PBS) solution, the linear range was 2.0×10-7~1.0×10-4 mol/L, and the detection limit was 6.0×10-8 mol/L (S/N=3). The sensor has good sensitivity, strong anti-interference ability, and good reproducibility and stability. The prepared biosensor was applied in the detection of salbutamol in food with a recovery of 86.5%~111.9%（n=3), and the results were satisfactory.
