▎ 摘　　要

NOVELTY - A modified electrode is obtained by carrying out polyacrylamide-graphene/nano-palladium modification on the bromine-containing modified electrode. USE - Modified electrode for highly sensitive detection of ethanol. ADVANTAGE - The modified electrode is prepared by simple process, and performs electrocatalytic reduction of ethanol, due to the special macromolecule effect and the interaction between the polyacrylamide-graphene composite carrier and the catalytic center, reaction substrate and product, and performs rapid detection (150 seconds) with high sensitivity of 1.3x 109 mol/L. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for preparing modified electrode for highly sensitive detection of ethanol, which involves (a) placing bromine-containing modified electrode in solution composed of 0.2-1 mol/L acrylamide, 0.5x 10-4-2.5x 10-4 moL/L fluorescein, 2x 10-3-8x 10-3 moL/L triethylamine and 10-20 mol/L absolute ethanol, vacuuming, irradiating with LED for 3-8 hours to obtain polyacrylamide modified electrode, (b) dissolving carboxylated graphene in buffer solution with pH of 5.0, ultrasonically mixing to prepare 0.5-2 mg/mL graphene solution, preparing mixed solution composed of 0.01-0.05 mol/L nitrogen hydroxysuccinimide and 0.05-0.2 mol/L carbodiimide solution, adding mixed solution to the graphene solution, immersing polyacrylamide-modified electrode in mixed solution for 0.5-2 hours to obtain polyacrylamide-graphene modified electrode, (c) placing the polyacrylamide-graphene modified electrode in an electrolyte containing 0.5-3.5 mmol/L palladium chloride, electrodepositing at a potential of -1.0 V for 30-120 seconds, removing the electrode, washing with ultrapure water and naturally drying to obtain final product.