拉贝洛尔在nano-Fe₃O₄-多壁碳纳米管复合修饰玻碳电极上的电催化氧化及电分析方法

目的: 研究拉贝洛尔(labetalol,LBT)在nano-Fe₃O₄与多壁碳纳米管(Multi-walled carbon nanotubes,MWCNTs)复合修饰玻碳电极(nano-Fe₃O₄-MWCNTs/GCE)上的电化学行为及电化学动力学性质,建立LBT电化学定量测定方法。方法: 循环伏安法(Cyclic Voltammetry,CV),计时电流法(Chronoamperometry,CA),方波伏安法(Square Wave Voltammetry,SWV)以及电化学交流阻抗谱(EIS)。结果: 在nano-Fe₃O₄-MWCNTs/GCE上LBT发生了一受扩散控制的不可逆电化学氧化过程。考查了实验条件对LBT伏安行为的影响,测定了LBT在nano-Fe₃O₄-MWCNTs/GCE上的电极反应过程动力学参数。用SWV法测得LBT氧化峰电流与其浓度在1.0 × 10^-5×1.0 × 10^-3 mol·L^-1呈线性关系,检出限(S/N=3)为1.0 × 10^-5 mol·L^-1。并用本方法对市售LBT片进行了电化学定量测定,RSD在0.4%~0.9%之间,加标回收率在99.70%~103.0%之间。结论: nano-Fe₃O₄-MWCNTs/GCE对LBT电化学氧化具有良好的催化作用,该方法可用于市售LBT片中LBT含量的电化学定量测定。

Objective: To study the electrochemical behaviors and electrochemical kinetics of labetalol(LBT)at nano-Fe₃O₄-multi-wall carbon nanotubes modified glassy carbon electrode(nano-Fe₃O₄-MWCNTs/GCE),so as to establish an LBT electrochemical quantitative assay.Methods: Cyclic voltammetry(CV),Chronoamperometry(CA),Square wave voltammetry(SWV)and electrochemical impedance spectrum(EIS)were applied.Results: Electrochemical experimental results showed that LBT electrochemical behavior in 0.10 mol·L^-1PBS exhibited an irreversible electrochemical oxidation process at nano-Fe₃O₄-MWCNTs/GCE.The influence of the experimental conditions on the voltammetric behaviors of LBT was also examined,and the kinetic parameters of the electrode reaction process were determined.The relationship between LBT oxidation peak current and its concentration was evaluated by square wave voltammetry(SWV).The experimental results showed a good linear relationship between the oxidation peak currents of LBT and its concentration in the range of 1.0 × 10^-5-1.0 × 10^-3 mol·L^-1.The detection limit was 1.0 × 10^-5 mol·L^-1.The quantitative determination of LBT content was investigated,the relative standard deviation is between 0.4%-0.9% and the recovery rate is in the range of 99.70%-103.0%. Conclusion: The experimental results indicated that nano-Fe₃O₄-MWCNTs/GCE could be a good catalyst for the oxidation of LBT. Furthermore,this method can be applied in the determination of commercial LBT content with simple manipulation.