▎ 摘　　要

NOVELTY - Preparing aptamer sensor for detecting kanamycin residue comprises using covalent bond and self-assembling technique to construct an aptamer sensor, introducing thionine, graphene oxide-polyaniline nano-gold and other material, enhancing electrochemical properties of aptamer sensor, using kanamycin aptamer and kanamycin specific binding to fix kanamycin, and quickly detecting kanamycin target component. The graphene-polyaniline nano-composite film is prepared by preparing graphene oxide and graphene-polyaniline nano composite material, adding in dispersing medium, and filtering. USE - The method is useful in preparing aptamer sensor for detecting kanamycin residue (claimed). ADVANTAGE - The composite film uses thionine, gold nanoparticles and other materials to increase the electrode surface electro-conductivity and stability qualitative, and makes the electrode surface having better aptamers antibiotic fixing ability. The sensor has high stability and provides good interface for fixeing kanamycin, maintains the biological activity of kanamycin and improves the fixed amount of kanamycin aptamer; has high sensitivity, good stability and good specificity; and provides good recovery rate is in accordance with the requirements. DETAILED DESCRIPTION - Preparing aptamer sensor for detecting kanamycin residue comprises using covalent bond and self-assembling technique to construct an aptamer sensor used for detecting kanamycin antibiotic, and introducing thionine, graphene oxide-polyaniline nano-gold and other material, enhancing the electrochemical properties of aptamer sensor, using kanamycin aptamer and kanamycin specific binding to fix kanamycin, and quickly detecting kanamycin target component, where the graphene-polyaniline nano-composite film is prepared by (i) preparing graphene oxide: adding graphite oxide powder slowly into sodium nitrate and sulfuric acid solution containing potassium permanganate and hydrogen peroxide mixture, when there is no gas-generation, adding excess ultra-pure water in the mixture, filtering the reaction mixture, washing the filtrate using hydrochloric acid aqueous solution and ultra-pure water, dissolving in ultra-pure water, and filtering to remove the impurity, centrifuging the filtrate for 30 minutes to remove the residual graphite, and then obtaining the graphene oxide, and (ii) preparing graphene-polyaniline nano composite material: dissolving 0.3 mol/l aniline in 1 mol/l hydrochloric acid solution, adding graphene oxide into mixed solution and carrying out ultrasonic process for 1 hour, then adding 0.075 mol/l 10 ml ammonium persulfate and 1 mol/l hydrochloric acid solution quickly into the mixture under vigorous stirring, polymerizing aniline after 5 minutes, at the same time, when the color of mixture turns into green, stirring overnight at room temperature (RT), filtering the mixture and diluting using 100 ml ultra-pure water, and filtering and collecting the obtained graphene-polyaniline composite material, adding it into the dispersing medium containing 0.1 ml hydrazine and 50 ml ultra-pure water, heating at 95 degrees C for 1 hour, then filtering the composite material, washing repeatedly using ultra-pure water to remove hydrazine, dispersing the obtained composite material in 10 ml of ammonium persulfate (0.06 g) containing 1 mol/l hydrochloric acid, stirring at room temperature overnight, collecting the separated polymer by filtration, washing repeatedly using ultra-pure water, ethanol and hexane, filtering and collecting the obtained graphene-polyaniline nano-composite material.