Department of Chemistry, Yazd University, Yazd, 89195-741, Iran.
Analyst. 2011 Nov 7;136(21):4595-602. doi: 10.1039/c1an15346c. Epub 2011 Sep 20.
In this study, an acetaminophen-modified glassy carbon electrode (ACMGCE) was fabricated for the purpose of investigating its electrochemical behavior by cyclic voltammetry (CV). ACMGCE serves as an excellent bifunctional electrocatalyst for the oxidation of ascorbic acid (AA) and glutathione (GSH) in a phosphate buffer solution (pH 7.0). The kinetic parameters such as the electron transfer coefficient, α, and the heterogeneous electron transfer rate constant, k', for the oxidation of AA and GSH at the ACMGCE surface were determined by CV. In addition, detection limits of 3.89 μM for AA and 0.37 μM for GSH were obtained at the ACMGCE using a differential pulse voltammetric (DPV) method. In DPV, the bifunctional modified electrode could separate the oxidation peak potentials of AA, GSH, adrenaline (AD) and tryptophan (Trp) present in the same solution, though the peak potentials were indistinguishable at a bare GCE. Finally, the modified electrode was successfully applied to the determination of AA in a pharmaceutical preparation and GSH in a human plasma sample.
本研究制备了一种对乙酰氨基酚修饰的玻碳电极（ACMGCE），并通过循环伏安法（CV）来研究其电化学行为。ACMGCE 作为一种出色的双功能电催化剂，可用于在磷酸盐缓冲溶液（pH 7.0）中氧化抗坏血酸（AA）和谷胱甘肽（GSH）。通过 CV 确定了在 ACMGCE 表面上 AA 和 GSH 氧化的动力学参数，如电子转移系数α和非均相电子转移速率常数 k'。此外，使用差分脉冲伏安法（DPV）在 ACMGCE 上获得了 AA 的检测限为 3.89 μM，GSH 的检测限为 0.37 μM。在 DPV 中，双功能修饰电极可以分离出同一溶液中存在的 AA、GSH、肾上腺素（AD）和色氨酸（Trp）的氧化峰电位，尽管在裸 GCE 上这些峰电位无法区分。最后，该修饰电极成功地应用于测定药物制剂中的 AA 和人血浆样品中的 GSH。
