醋氯芬酸在多壁碳纳米管修饰电极上的电催化氧化及电分析方法

Electrocatalytic Oxidation of Aceclofenac at Multi-wall Carbon Nanotubes Modified Glassy Carbon Electrode and Its Electrochemical Determination

关键词:  醋氯芬酸  碳纳米管修饰电极  电催化氧化  电分析方法  电化学动力学

Key words:  aceclofenac  carbon nanotube modified glassy carbon electrode  electrocatalytic oxidation  electrochemical determination  electrochemical kinetics

摘要:

目的 研究醋氯芬酸(aceclofenac，AC)在多壁碳纳米管修饰玻碳电极(MWCNTs/GCE)上的电化学氧化行为及电化学动力学性质，据此建立AC电化学定量测定方法。方法 采用循环伏安法(CV)，计时电流法(CA)，方波伏安法(SWV)。结果 AC在GCE上于0.59 V处出现一氧化峰，与在GCE上相比，AC在MWCNTs/GCE上峰电位基本不变，峰电流增大约8倍。同时考察了实验条件对AC伏安行为影响，测定了电极反应过程动力学参数，并采用SWV研究了AC氧化峰电流与浓度之间的关系，表明氧化峰电流与其在2.0×10^-6~2 .0×10^-4 mol·L^-1内呈良好的线性关系，检出限(S/N=3)1.2×10^-7 mol·L^-1。加样回收率在98.8%~105.0%之间，RSD在1.1%~2.8%之间。结论 AC电催化氧化是一受扩散控制的不可逆电极反应过程，MWCNTs/GCE对AC电化学氧化具有良好的催化作用，据此建立的电化学测定方法可用于市售AC药品含量的电化学定量测定。

Abstract:

OBJECTIVE To investigate electrocatalytic oxidation and electrochemical kinetics of aceclofenac (AC) at multi-wall carbon nanotube modified glassy carbon electrode (MWCNTs/GCE), and to establish its electrochemical quantitative determination method. METHODS Cyclicvoltammetry(CV), chronoamperometry(CA) and square wave voltammetry(SWV) were used. RESULTS One oxidation peak of AC was occurred at 0.59 V on GCE, while on MWCNTs/GCE, the oxidation peak potential of AC was almost the same, however, the oxidation peak current increased about 8 times of AC compared with that on GCE. At the same time, the influence of the experimental conditions on the voltammetric behaviors of AC was also examined as well, and the kinetic parameters of the electrode reaction process were determined. The relationship between AC oxidation peak current and its concentration was evaluated by SWV. The experimental results showed that the oxidation peak currents of AC versus its concentration had a good linear relationship in the concentration range of 2.0×10^-6-2.0×10^-4 mol·L^-1 with the detection limit of 1.2×10^-7 mol·L^-1. The recovery was in the range of 98.8%-105.0% and the relative standard deviation was between 1.1%-2.8%. CONCLUSION The electrocatalytic oxidation of AC is an irreversible electrode reaction process which is diffusion-controlled and MWCNTs/GCE shows a quite good catalytic effects towards the electrochemical oxidation of AC, and the established electrochemical determination can be applied in the quantitative determination of AC content for the commercial AC pharmaceuticals.