▎ 摘　　要

NOVELTY - Preparing trace fast nitrogen electrochemical sensor involves placing the glassy carbon electrode in an aqueous solution containing potassium perchlorate and sodium carbonate, and activating by cyclic voltammetry to obtain an activated glassy carbon electrode, dropping the graphene oxide aqueous dispersion on the surface of the activated glassy carbon electrode, and drying naturally to obtain the graphene oxide modified activated glassy carbon electrode. The obtained graphene oxide modified activated glassy carbon electrode is placed in a supporting electrolyte solution containing bromocresol green, and the polybromocresol green-graphene nanocomposite film modified activated glassy carbon electrode is prepared by electrochemical polymerization. The polybromocresol green-graphene nanocomposite film modified activated glassy carbon electrode is placed in Nafion solution, and scanning by cyclic voltammetry to obtain product. USE - Method for preparing trace fast nitrogen electrochemical sensor used in detecting the concentration of NO released by biological samples (claimed). ADVANTAGE - The electrochemical sensor has loose and porous electrode surface, large specific surface area, fast electron transfer rate, catalytic effect, short response time, wide linear range, high sensitivity, good selectivity and good stability.