▎ 摘　　要

NOVELTY - Preparing nano tin/pyridine functionalized graphene modified electrode, comprises synthesizing pyridine functionalized graphene oxide (Py-GO), tin nanoparticles/pyridine functionalized graphene (SnNPs/Py-RGO) synthesis and tin nanoparticles/pyridine functionalized graphene modified electrode (SnNPs/Py-RGO/GCE) preparation. The Py-GO is synthesized by mixing Py-GO aqueous solution and SnCl2 hydrochloric acid solution, ethylenediaminetetraacetic acid is added to form a mixed solution and stirred in a water bath. The deionized water and hydrazine hydrate are added, and the reaction is centrifuged to wash and dry. USE - Method for preparing nano tin/pyridine functionalized graphene modified electrode used for simultaneous detection of ascorbic acid and nitrite (claimed). ADVANTAGE - The method enables to prepare nano tin/pyridine functionalized graphene modified electrode, which has uniform particle size and are uniformly distributed on the surface of graphene without agglomeration, greatly improves the catalytic activity and electronic conductivity of the modified electrode, and has excellent detection sensitivity for nitrite and ascorbic acid, where the detection limits are 0.006 and 0.019 micro M, respectively. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing nano tin/pyridine functionalized graphene modified electrode, which comprises (A) mixing graphene oxide and pyridine with ultrasonic for 5-10min, reacting at 60-70 degrees C for 40-48h, washing with benzene and acetone after the reaction, and drying at 60 degrees C for 12h; (B) dispersing 1mg/L Py-GO in deionized water with ultrasound, and mixing the Py-GO aqueous solution and SnCl2 hydrochloric acid solution in a volume ratio of 60:1 to 1.5, and then adding ethylenediaminetetraacetic acid to form a mixed solution, where the mass-volume ratio of ethylenediaminetetraacetic acid and Py-GO aqueous solution is 1mg:9-10mL, stirring in a water bath at 60-70 degrees C, with stirring rate of 2000-3000r/min; (C) adding deionized water and hydrazine hydrate, where the volume ratio of Py-GO aqueous solution, deionized water and hydrazine hydrate is 3:1:1; (D) heating the reaction for 20-30 minutes, then centrifuging and drying, dissolving SnCl2 in hydrochloric acid with a concentration of 0.1 mol/mL with the mass-volume ratio of SnCl2 and hydrochloric acid is 1mg:15mL; (E) polishing the glassy carbon electrode (GCE, =3mm) with alumina powder with a particle size of 0.5 micro m and 0.03 micro m; and (F) using deionized water, ethanol and deionized water to ultrasonically clean in sequence, taking 8 mL of SnNPs/Py-RGO aqueous solution with a concentration of 2 mg/L and applying to the surface of GCE, and letting it dry naturally.