▎ 摘　　要

NOVELTY - Electrochemical immune sensor for detecting tiamulin antigen, is claimed. The surface of the base electrode has modified layer of gold/silver-graphene oxide-perfluorosulfonic acid nano-compound material. The modified layer is fixed with anti-tiamulin monoclonal antibody. The outermost layer is bovine serum albumin. USE - Used as electrochemical immune sensor for detecting tiamulin antigen. ADVANTAGE - The sensor: reduces the silver nanoparticles to graphene oxide in situ to obtain the silver-graphene oxide nano-compound material; exhibits excellent conductivity and redox activity; has excellent film-forming ability and high chemical stability; uses perfluorosulfonic acid as dispersant to obtain silver-graphene oxide-nitrogen fluoride compound solution, and the compound solution to modify the surface of the base electrode; is simple, efficient and sensitive; detects tiamulin antigen with wider detection range and lower detection limit; and has excellent accuracy when applied to the detection of tiamulin residues in animal-derived foods e.g. eggs, pork and pig liver. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing the electrochemical immune sensor for detecting tiamulin antigen (1) pre-treating basic electrode, (2) preparing silver-graphene oxide-perfluorosulfonic acid compound solution, dropping the compound solution on the basic electrode pretreated in the step (1), and drying at room temperature, (3) soaking the electrode obtained in the step (2) in chloroauric acid solution, depositing gold nanoparticles by constant potential deposition method, depositing -0.2 V constant potential for 600-800 seconds, washing the surface of the electrode, and drying it to obtain modified electrode, (4) dropping the anti-tiamulin monoclonal antibody solution onto the modified electrode obtained in the step (3), incubating, washing the surface of the electrode after the incubation, drying, dropping the bovine serum albumin solution onto the modified electrode, washing the electrode surface after incubation, drying to obtain electrochemical immune sensor for detecting tiamulin antigen; and (2) detecting tiamulin antigens by the electrochemical immune sensor for detecting tiamulin antigens, comprises (i) using the electrochemical immune sensor for detecting tiamulin antigen as working electrode, reference electrode and counter electrode to form three-electrode system, carrying out electrochemical measurement of tiamulin antigen by differential pulse voltammetry in phosphate buffered saline buffer solution, and obtaining fitting linear regression equation of the electrochemical immune sensor to tiamulin antigen, and (ii) using the electrochemical immune sensor for detecting tiamulin antigen as working electrode, reference electrode and counter electrode to form three-electrode system, carrying out electrochemical measurement of the sample to be tested by differential pulse voltammetry in the phosphate buffered saline buffer solution, using the fitting linear regression equation of the step (i), and calculating the concentration of tiamulin in the sample to be tested.