论文部分内容阅读
目的:研究了N-乙酰-L-半胱氨酸(N-Acetyl-L-Cysteine,NAC)在多壁碳纳米管修饰玻碳电极(MWCNT/GCE)上的电化学行为及电分析方法。方法:运用循环伏安法(CV)、计时库仑法(CC)、计时电流法(CA)、线性扫描伏安法(LSV)。结果:NAC在GCE上的直接电化学氧化十分迟缓,无氧化峰出现,而在MWCNT/GCE上于0.15V处出现一个不可逆氧化峰。研究了实验条件对NAC电化学行为的影响。测定了电催化过程动力学参数:扩散系数D为5.26×10-5cm2.s-1,电子转移系数α为0.55,电极反应速率常数kf为7.95×10-3s-1。对含NAC的药物进行电化学定量测定,RSD%在1.2%～2.4%之间,加标回收率在101.6%～102.2%之间。结论:MWCNT/GCE对NAC具有良好的电催化氧化作用,是一受扩散控制的不可逆电催化氧化过程,对NAC样品含量进行电化学定量测定,测定结果令人满意。
OBJECTIVE: To study the electrochemical behavior of N-Acetyl-L-Cysteine (NAC) on multiwalled carbon nanotubes modified glassy carbon electrode (MWCNT / GCE) and its analytical method. Methods: Cyclic voltammetry (CV), chrono-coulometry (CC), chronoamperometry (CA) and linear sweep voltammetry (LSV) were used. Results: The direct electrochemical oxidation of NAC on GCE was very slow, no oxidation peak appeared, and an irreversible oxidation peak appeared at 0.15V on MWCNT / GCE. The influence of experimental conditions on the electrochemical behavior of NAC was studied. The kinetic parameters of the electrocatalytic process were determined. The diffusion coefficient D was 5.26 × 10-5cm2.s-1, the electron transfer coefficient α was 0.55, and the electrode reaction rate constant kf was 7.95 × 10-3s-1. Electrochemical quantitative determination of drugs containing NAC, RSD% of 1.2% to 2.4%, the recovery of the standard between 101.6% ~ 102.2%. CONCLUSION: MWCNT / GCE possesses good electrocatalytic oxidation of NAC and is an irreversible electrocatalytic oxidation process controlled by diffusion. The content of NAC is electrochemically and quantitatively determined. The results are satisfactory.