以对乙酰氨基酚为电催化介质同时测定谷胱甘肽和酪胺

Simultaneous Voltammetric Determination of Glutathione and Tyramine with Acetaminophen as an Electrocatalytic Mediator

研究了在多壁碳纳米管/石墨烯纳米片(MWCNTs/GRs)杂化材料修饰的玻碳电极上,以对乙酰氨基酚(AP)为媒介电催化氧化谷胱甘肽(GSH),并同时测定GSH和酪胺(TA)的伏安方法。AP对GSH有明显的电催化作用且MWCNTs/GRs可有效放大电信号。实验探讨了pH值对电流响应和峰电位差的影响。在最佳实验条件下,用差分脉冲伏安法(DPV)测得GSH和TA的峰电流与其浓度分别在0.75~20μmol·L^(-1)和2.5~125μmol·L^(-1)浓度范围内呈线性关系,检测限(S/N=3)分别为0.15μmol·L^(-1)和0.92μmol·L^(-1)。该方法应用于同时测定牛奶中GSH和TA的含量,获得较好效果。

A novel voltammetric method was proposed for separation and determination of glutathione（GSH）and tyramine（TA）at multi-walled carbon nanotubes and graphene nano hybrid material modified glassy carbon electrode（MWCNTs/GRs/GCE）.GSH could be detected at much lower potential by introducing acetaminophen（AP）as a electrocatalytic mediator.MWCNTs/GRs could effectively amplify current signal.The electrochemical behavior of GSH and TA in the presence of AP was studied at MWCNTs/GRs/GCE and complete separation of anodic peaks was achieved.Under the optimum conditions,the electrocatalytic oxidation peak current of GSH showed a linear dependence on its concentration in the range of 0.75-20μmol·L^-1 with the detection limit of 0.15μmol·L^-1（S/N=3）,while the oxidation peak current of TA was linear to its concentration from 2.5μmol·L^-1 to 125μmol·L^-1 with the detection limit of 0.92μmol·L^-1（S/N=3）by differential pulse voltammetry（DPV）.The established method has been applied to the simultaneous determination of GSH and TA in milk with satisfactory results.