替硝唑在离子液体-碳纳米管复合修饰电极上的电催化还原及电分析方法

Electrocatalytic Reduction of Tinidazole at Room Temperature Ionic Liquid-Multi-Wall Carbon Nanotubes Modified Electrode and Its Electrochemcal Determination

关键词:  替硝唑  离子液体-多壁碳纳米管修饰电极  电催化还原  电分析方法

Key words:  tinidazole  ionic liquid-carbon nanotubes modified electrode  electrocatalyticl reduction  electroanalitical methods

摘要:

目的 研究替硝唑(TNZ)在玻碳电极(GCE)，多壁碳纳米管修饰电极(MWCNTs/GCE)及疏水性室温离子液体(RTIL)1-丁基-3-甲基咪唑六氟磷酸盐(BMIMPF6)-多壁碳纳米管(MWCNT)修饰电极(RTIL-MWCNTs/GCE)上的电化学行为，电化学动力学性质及电化学定量分析方法。方法 运用循环伏安法(CV)、计时库仑法(CC)、计时电流法(CA)、方波伏安法(SWV)、稳态电流-时间曲线及电化学交流阻抗谱。结果 与GCE相比，TNZ在RTIL-MWCNTs/GCE上的还原峰电位正移了105 mV，还原峰电流增大了约5倍；与MWCNTs/GCE相比，其还原峰电位稍有负移，但还原峰电流增大。TNZ 在RTIL-MWCNTs/GCE上的还原峰电流与浓度在5.0×10^-5~1.0×10^-2 mol·L^-1内呈良好线性关系，检出限为2.4×10^-6 mol·L^-1。加标回收率在98.7%~100.2% 之间，RSD在0.64%~1.65%之间。结论 RTIL-MWCNTs/GCE对TNZ电化学还原具有良好的催化作用，是一受扩散控制的不可逆电极反应过程，该方法可用于TNZ含量的电化学定量测定，操作简便快捷，测定结果符合定量测定要求。

Abstract:

OBJECTIVE Electrochemical behaviors, electrochemical kinetics and electrochemical quantitative determination of tinidazole (TNZ) at glassy carbon electrode (GCE) and room temperature ionic liquid-multi-wall carbon nanotubes modified glassy carbon electrode (RTIL-MWCNTs/GCE) were investigated. METHODS Cyclic voltammetry (CV), chronocoulometry (CC), chronoamperometry (CA), square wave voltammetry (SWV), amperometric I-t curve and alternating current-inpedance (AC-inpedance). RESULTS The reduction peak current of TNZ increased at RTIL-MWCNTs/GCE in comparison with that at the bare GCE and MWCNTs/GCE. At RTIL-MWCNTs/GCE, the reduction peak current was proportional to TNZ concentration over the range of 5.0×10^-5-1.0×10^-2 mol·L^-1. The detection limit was 2.4×10^-6 mol·L^-1. The relative standard deviation was between 0.64%-1.65% and the recoverage was in the range of 98.7%-100.2%. CONCLUSION RTIL- MWCNTs/GCE could catalyze TNZ electrochemical reduction very well, and it was a diffusion-limited electrochemical process. The proposed method could be applied in the electrochemical determination of TNZ content in injection samples with the satisfied results.