▎ 摘　　要

novel kind of structurally uniform and electrocatalytic activity material formed by combination of graphene (GR), 1-(6,7- dihydroxy-2,4-dimethylbenzofuran-3-yl) ethanone (DE) and ionic liquid (IL) and used to modify carbon paste electrode (GR-DE-IL/CPE). The electrochemical properties of DE (as a modifier) in graphene paste electrode-based ionic liquids were studied in the aqueous solution. The fabricated GR-DE- IL/CPE was further used for the successful determination of levodopa (LD), and it exhibited an excellent electrocatalytic activity toward LD with a lower overvoltage, good electrochemical performances with higher conductivity and lower electron transfer resistance. It has been found that under optimum condition in CV, the oxidation of LD occurs at a potential about 400 mV less positive than that of an unmodified carbon paste electrode. Based on differential pulse voltammetry, the oxidation of LD exhibited a dynamic range between 0.015 and 1000 mu M and a detection limit (3 sigma) of 5.0 +/- 1 nM. Finally, this method was used for the determination of LD in real samples, using standard addition method. (C) 2014 Elsevier B.V. All rights reserved.