将利用电化学法制备的石墨烯溶于N，N-二甲基甲酰胺溶液中超声分散1 h，并滴涂在玻碳电极表面，构建了一种基于石墨烯修饰电极的电化学传感器。利用循环伏安法和线性扫描伏安法探究了4-氯苯氧乙酸在该修饰电极上的电化学行为，差分脉冲伏安法检测了4-氯苯氧乙酸的浓度。结果表明，该传感器在浓度为0.5~100 μmol/L的范围内呈良好的线性关系，最低检出限为0.13 μmol/L（S/N=3）。具有良好的稳定性和抗干扰能力，将其应用于黄豆芽中的4-氯苯氧乙酸的检测，回收率为93.36%~101.40%。

Graphene prepared by electrochemical method is dissolved in N,N-dimethyl formamide solution and dispersed by ultrasound for 1 hour.An electrochemical sensor based on graphene-modified electrode is constructed by coating the dispersed graphene on the surface of glassy carbon electrode.The electrochemical behavior of 4-chlorophenoxyacetic acid on the graphene-modified electrode is investigated by cyclic voltammetry and linear scanning voltammetry,and the concentration of 4-chlorophenoxyacetic acid is determined by differential pulse voltammetry.The results show that the sensor has a good linear relationship in the concentration range of 0.5-100 μmol·L^-1,and the minimum detection limit is 0.13 μmol·L^-1 (S/N=3).It exhibits a good stability and strong anti-interference ability.As it is applied to the detection of 4-chlorophenoxyacetic acid in soybean sprouts,the recovery rate is in the range of 93.36%-101.4%.