▎ 摘　　要

NOVELTY - An electrochemical sensor preparing method involves preparing aqueous chloroauric acid, graphene dispersed liquid and graphene-nanogold complex, modifying glass carbon electrode and preparing graphene-nanogold sensor. The graphene-nanogold complex is prepared by heating graphene dispersion and aqueous chloroauric acid, adding 1% trisodium citrate solution to mixture, filtering liquid, grinding solid, and dispersing powder in ethyl alcohol. The glass carbon electrode is modified by dropping graphene-nanogold suspension onto polishing glass carbon electrode, and drying electrode. USE - Method for preparing electrochemical sensor that is utilized in detecting fixed amount of glucose (all claimed). ADVANTAGE - The method enables preparing electrochemical sensor with high sensitivity, wide range and low detection limits, increasing high activity of modified electrode, large surface area and transfer rate, and enhancing property of glucose. DETAILED DESCRIPTION - An electrochemical sensor preparing method, involves preparing aqueous chloroauric acid, preparing graphene dispersed liquid, preparing graphene-nanogold complex, modifying glass carbon electrode with the graphene-nanogold complex and preparing graphene-nanogold sensor. The aqueous chloroauric acid is prepared by dissolving chloroauric acid in deionized water in mass volume ratio (g/ml) of 1:100-200, and stirring the mixture at 30-50 degrees C and speed of 300-450 revolutions/minute for 15-40 minutes. The graphene dispersed liquid is prepared by dispersing graphene in deionized water ultrasonically for 20 minutes to obtain graphene dispersion, and mixing the graphene dispersion with aqueous chloroauric acid, where the mass volume ratio (g/ml) of the graphene and deionized water is 1:500-1000, and volume ratio of the graphene dispersion and aqueous chloroauric acid is 100:1-5. The graphene-nanogold complex is prepared by heating graphene dispersion and aqueous chloroauric acid in oil bath at constant temperature of 92-98 degrees C, adding 1% trisodium citrate solution to the mixture, stirring the mixture continuously for 50-90 minutes to obtain purple-red liquid, filtering the liquid to obtain solid, grinding the solid, and dispersing powder in anhydrous ethyl alcohol and stirring the mixture at 1500-3000 revolutions/minute, where the volume ratio of the trisodium citrate solution and chloroauric acid is 1-2:1, and mass volume ratio (g/ml) of the graphene-nanogold complex and anhydrous ethyl alcohol is 1:100-500. The glass carbon electrode is modified by washing glass carbon electrode with deionized water for 2-5 times, polishing glass carbon electrode with alumina to smooth surface, dropping 1-5 mu l graphene-nanogold suspension onto the glass carbon electrode, polishing the glass carbon electrode, and drying the glass carbon electrode in vacuum-drying chamber for 24-48 hours to obtain graphite-nanogold modified electrode. The graphene-nanogold sensor is prepared by adding the obtained graphite-nanogold modified electrode and reference electrode to electrochemical sensor device. An INDEPENDENT CLAIM is also included for an electrochemical sensor prepared by the above-mentioned method.