▎ 摘　　要

NOVELTY - Detection of amaranth in food comprises preparing porous graphene (PG); modifying glassy carbon electrode (GCE) with PG to obtain PG/GCE electrode; using PG/GCE electrode as working electrode in three-electrode system, placing three-electrode system in Britton-Robinson (BR) buffer solution containing amaranth, subjecting to square wave stripping voltammetry, and calculating linear regression equation of amaranth; and preparing sample solution, subjecting to square wave stripping voltammetry, and substituting obtained oxidation peak current value of amaranth in linear regression equation. USE - Method for detecting amaranth in food (claimed). ADVANTAGE - The method is simple, has high sensitivity and low detection limit, and provides accurate results. DETAILED DESCRIPTION - Detection of amaranth in food by using porous graphene comprises: (A) dissolving nickel nitrate (Ni(NO3)2) powder in deionized (DI) water and adding graphene oxide (GO) solution under stirring, in which GO-Ni weight ratio is 10:1; ultrasonically mixing, quickly transferring into freeze-dryer, vacuum freezing with liquid nitrogen at less than 0 degrees C for 48 hours, heating in tubular furnace from room temperature to 800 degrees C at 10 degrees C/minute, and holding in flowing argon atmosphere for 1 hour to obtain black solid powder; and washing black powder with dilute hydrochloric acid to form pores on graphene surface, rinsing with DI water, and vacuum drying to obtain porous graphene (PG); (B) polishing glassy carbon electrode (GCE) with alpha -alumina powder emulsion, and rinsing; and ultrasonically dispersing PG in high-purity water, coating obtained PG dispersion on cleaned GCE surface, and drying under infrared lamp to obtain PG/GCE electrode; (C) using PG/GCE electrode as working electrode, saturated calomel electrode as reference electrode and platinum electrode as auxiliary electrode, forming three-electrode system; placing three-electrode system in Britton-Robinson (BR) buffer solution of pH 7 containing 5x 10-6 mol/L amaranth, stirring under open circuit condition for 210 seconds, standing for 10 seconds, cyclic voltammetry scanning at 0.5-1 V, and recording cyclic voltammetry curve to study electrochemical behavior of amaranth on PG/GCE surface, in which amaranth oxidation peak current in PG/GCE is enhanced; scanning different concentrations of amaranth by square wave stripping voltammetry at 0.5-1 V, recording square wave voltammetry curve, and reading amaranth oxidation peak current value; and using amaranth concentration abscissa and peak current value as ordinate, drawing standard curve in the range of 5x 10-9 to 1x 10-6 mol/L, with detection limit of 0.8x 10-10 mol/L, and calculating linear regression equation of amaranth according to I( mu A)=45.77x C( mu M)-0.18, which is used for determining concentration of amaranth in actual sample; and (D) putting sample in volumetric flask and fixing volume with BR buffer solution of pH 7; and subjecting test sample solution to square wave stripping voltammetry to obtain oxidation peak current value of amaranth, and substituting obtained current value in the linear regression equation obtained in step (C) to obtain concentration of amaranth in sample. INDEPENDENT CLAIMS are included for: (1) preparation of PG material by performing step (A); and (2) preparation of PG/GCE by performing step (B).