▎ 摘　　要

NOVELTY - Electrochemical sensor electrode surface nano material modification method comprises using carbon paper as working electrode substrate, modifying graphene, sulfur and nano gold on the surface of working electrode to form composite bio-sensitive film, immobilizing specific antibody on the bio-sensitive membrane and antigen concentration is proportional to the degree of reduction of the reaction current to achieve antigen detection. USE - The method is useful for electrochemical sensor electrode surface nano material modification. ADVANTAGE - The method can realize high-sensitivity detection of trace amounts of cancer proteins and polypeptide molecules. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) electrochemical sensor, comprising sensor body, where top surface of the carbon electrode of the sensor body is sequentially provided with graphene nano layer, thionine layer and nano gold layer and nano gold layer is fixed with a specific antibody; and (2) detecting electrical sensor, comprising dripping antigen to be detected on the surface of biosensor and binding antibody specifically to the antigen of analyte to generate an electric field change, using differential voltammetric pulse method of current suppression to detect weak reaction current of antibody and antigen and converting antigen concentration by principle that antigen concentration is proportional to the degree of decrease of the reaction current.