▎ 摘　　要

NOVELTY - Preparing silver-loaded nano-particle of graphene/glassy carbon electrode (Ag-NG/GCE) electrochemical sensor involves adding graphene oxide of specific mass into ultrapure water to form graphene oxide dispersion liquid, and placing dispersion liquid into ultrasonic processor for ultrasonic treatment for 1 hour to uniformly disperse the graphene oxide dispersion liquid. The glycine of specific mass is added into graphene oxide dispersion liquid after ultrasonic treatment, and stirred for 30 minutes to obtain a mixed liquid A. USE - Method for preparing Ag-NG/GCE electrochemical sensor is used for detecting bergenin by using a linear sweep voltammetry method as an analysis method (claimed). ADVANTAGE - The method enables to prepare silver-loaded nano-particle of amino graphene Ag-NG composite material that has good stability, good dispersibility, good stability and is modified on the glassy carbon electrode surface. The electrochemical sensor has high sensitive response to bergenin, which is applied to fast and accurate detection of Bergenin in actual sample. DETAILED DESCRIPTION - Preparing silver-loaded nano-particle of graphene/glassy carbon electrode (Ag-NG/GCE) electrochemical sensor involves adding graphene oxide of specific mass into ultrapure water to form graphene oxide dispersion liquid, and placing dispersion liquid into ultrasonic processor for ultrasonic treatment for 1 hour to uniformly disperse the graphene oxide dispersion liquid. The glycine of specific mass is added into graphene oxide dispersion liquid after ultrasonic treatment, and stirred for 30 minutes to obtain a mixed liquid A. The silver nitrate of of specific mass is added into mixed solution A, stirred continuously for 30 minutes to obtain mixed solution B', and using 0.5 moles/liter (mol/L) sodium hydroxide solution to adjust the pH value of the mixed solution B' to 9 to obtain a mixed solution C'. The mixed solution C' is stirred for 1 hour, mixed solution C' is transferred into a reaction kettle, reaction kettle is placed into oven, temperature of oven is set to be 130℃, and stirred mixed solution C' is reacted for 4 hours to obtain a reaction mixture. The obtained reaction mixture is cooled to room temperature, centrifugal separation is performed, supernatant is removed to obtain lower-layer precipitate, centrifugal washing is carried out on the precipitate with high-purity water, and vacuum drying is performed at 60℃ for 8-10 hours to obtain silver nanoparticle-loaded aminated graphene (Ag-NG). The Ag-NG of specific mass is added into ultrapure water to form Ag-NG dispersion liquid, where concentration of the Ag-NG in the dispersion liquid is 1 milligram/milliliter (mg/mL-1), dispersion liquid is placed into ultrasonic processor for uniform ultrasonic dispersion. An 0.3 micron (μm) of aluminum oxide is used to polish GCE to a mirror surface by using powder, and polished GCE is ultrasonically cleaned by using ultrapure water and ethanol. An 5 microliter (μL) of the Ag-NG dispersion liquid subjected to ultrasonic cleaning is dropped onto the surface of GCE subjected to ultrasonic cleaning, and GCE is placed under an infrared lamp to dry for 10 minutes to obtain the Ag-NG/GCE electrochemical sensor. An INDEPENDENT CLAIM is included for an application of Ag-NG/GCE electrochemical sensor, which is used for detecting bergenin.