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利用循环伏安法制备了L-组氨酸-赤藓红复合膜修饰玻碳电极(L-His-Erythrosine/GCE).采用扫描电镜(SEM)观察修饰电极的表面形貌结构,并用电化学阻抗谱(EIS)、循环伏安法(CV)表征修饰电极的电化学性能.在此基础上用差分脉冲伏安法(DPV)研究了对苯二酚(HQ)和邻苯二酚(CC)混合物在该电极上的电催化氧化,结果表明,L-His-Erythrosine/GCE对HQ及CC的电化学氧化具有显著的催化作用,两种异构体在该修饰电极上的氧化过电位明显降低,峰电流显著增大,二者氧化峰电位间隔达108m V,表明制备的修饰电极可用于HQ和CC的同时检测.在最佳实验条件下,HQ与CC浓度在1.2×10-6~1.1×10-4mol·L-1范围内与氧化峰电流呈良好线性关系,检出限分别为0.19μmol·L-1(HQ)和0.16μmol·L-1(CC)(S/N=3).另外,此修饰电极具有较好的重现性和较强的抗干扰能力,将修饰电极用于实际水样品中HQ和CC的测定,其加标回收率分别为99.9%~100.6%(HQ)、99.2%~100.2%(CC).
The L-His-Erythrosine / GCE was prepared by cyclic voltammetry. The surface morphology of the modified electrode was observed by scanning electron microscopy (SEM) Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to characterize the electrochemical performance of the modified electrode.On the basis of differential pulse voltammetry (DPV), the electrochemical properties of hydroquinone (HQ) and catechol The results showed that L-His-Erythrosine / GCE had a significant catalytic effect on the electrochemical oxidation of HQ and CC, and the oxidation potentials of the two isomers on the modified electrode Significantly decreased, the peak current increased significantly, the peak potential between the two reached 108mV, indicating that the prepared modified electrode can be used for simultaneous detection of HQ and CC under the best experimental conditions, HQ and CC concentration of 1.2 × 10-6 ~ 1.1 × 10-4 mol·L-1, the detection limits were 0.19μmol·L-1 (HQ) and 0.16μmol·L-1 (CC) respectively (S / N = In addition, the modified electrode has good reproducibility and strong anti-interference ability, the modified electrode was used for the determination of HQ and CC in the actual water samples, the spiked recoveries were 99 .9% to 100.6% (HQ), 99.2% to 100.2% (CC).