石墨烯/纳米金复合修饰电极对邻苯二酚和对苯二酚的同时测定

A Voltammetric Sensor Based on Graphene-Gold Nanocomposite Film for Simultaneous Determination of Hydroquinone and Catechol

目的:提出一种简单的石墨烯纳米金复合修饰玻碳电极(GO/GNPs/GCE)制备方法,并通过差分脉冲伏安法(DPV)法实现对对苯二酚(HQ)和邻苯二酚(CC)的同时检测。方法:采用交流阻抗法(ESI)研究了GO/GNPs/GCE修饰电极的性能,通过循环伏安法(CV)研究HQ和CC性能在GO/GNPs/GCE修饰电极上电化学行为。结果:HQ和CC在GO/GNPs/GCE比GCE上的氧化还原峰电流明显增加,且二者还原峰电位差可达110mV,可以实现二者同时灵敏检测,说明修饰电极电催化活性良好。在优化的实验条件下,GO/GNPs/GCE的DPV响应峰电流与HQ-CC浓度呈良好的线性关系,线性范围为2.0×10^(-5)～1.0×10^(-3) mol/L,检测下限为4.0×10^(-6) mol/L。结论:此修饰电极稳定性、选择性和重现性良好,可以应用于环境和医药领域中酚类物质的同时检测。

Objective:A new glassy carbon electrode modified with gold nanoparticles(GNPs)and coated with graphene(GO)film was fabricated via a simple method and used for simultaneous detection of hydroquinone(HQ)and catechol(CC).Methods:The electrochemical properties of GO/GNPs/GCE were studied with electrochemical impedance spectroscopy.The electrocatalysis capability of GO/GNPs/GCE was investigated by cyclic voltammetry(CV)and differential pulse voltammetry(DPV)techniques for HQ-CC assay.Results:Compared with the bare GCE,GO/GNPs/GCE exhibited outstanding electrocatalytic activity and both HQ and CC exhibited well-defined redox peaks and much larger peak currents at GO/GNPs/GCE.Due to the large separation of oxidation peak potentials(110 mV),the concentrations of HQ and CC can be easily determined simultaneously.Under the optimal conditions,the peak currents were linear to HQ/CC in the range from 2×10^-5 to 1×10^-3 mol/L.Conclusion:GO/GNPs/GCE exhibited excellent stability,selectivity and reproducibility,and they successfully applied in the determination of phenolic substance in the field of environment and medicine.