乙酰胆碱酯酶/Nafion/普鲁士蓝修饰玻碳电极的制备及其在有机农药检测中的应用

摘要

This paper reports the preparation of an acetylcholinesterase ( AChE) /Nafion/Prussian blue(PB)/ glass carbon electrode (GCE) and the electrochemical detection of pesticides such as carbaryl and trichlorfon. Atomic force microscopy and electrochemical technique were used to investigate the construction of the modified electrode and its effects on pesticide detection. Those results indicated that AChE dispersed uniformly in Nafion/PB/GCE. The AChE/Nafion/PB/GCE constructed under optimal conditions showed a good linear relationship between the peak current and the concentration of pesticide in the range of 0. 01 ~0. 5 (junol/L & 2. 0 ~ 10. 0 u,mol/L for carbaryl and 0. 02 ~ 1. 0 ujnol/L & 2. 0 ~ 8. 0 jjimol/L for trichlorfon, respectively. The limit of detection is 5. 0 nmol/L for carbaryl and 10. 0 nmol/L for trichlorfon, respectively. Furthermore the modified electrode was applied in the detection of analogous practical samples. It was found that the as-prepared sensor had high detection sensitivity, good reproducibility and anti-interference.%制备了乙酰胆碱酯酶/Nafion/普鲁士蓝修饰的玻碳电极,测试了该修饰电极检测有机农药西维因(carbaryl)和敌百虫(trichlorfon)的性能指标.利用原子力显微镜和电化学技术研究了电极的构造及其对于有机农药检测性能指标的影响.结果表明,乙酰胆碱酯酶均匀地分散到Nafion/普鲁士蓝修饰的玻碳电极上.在最优的实验条件下,构筑的修饰电极检测西维因和敌百虫的线性范围分别为0.01 ～0.5 μmol/L及2.0～10.0 μmoL/L和0.02～ 1.0 μmol/L及2.0～8.0 μmol/L,检出限分别为5.0和10.0 nmol/L.并对模拟的实际样品进行了检测,发现该方法有较高的检测灵敏度、较好的重复性和抗干扰性.