基于氧化锌纳米棒的乙酰胆碱酯酶生物传感器用于辛硫磷农药测定  

Determination of Phoxim Pesticides Using Acetylcholinesterase Biosensor Based on ZnO Nanorods

作　　者：谭琳[1] 卢旭晓[1] 白慧萍[1] 杨光明[1] 杨云慧[1] 

机构地区：[1]云南师范大学化学化工学院,昆明650092

出　　处：《理化检验（化学分册）》2009年第5期567-570,共4页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：云南省自然科学基金项目(No.2006B0028M);云南省教育厅自然科学基金(No.07Z10087)

摘　　要：以喷金的聚碳酸酯模板为工作电极，采用电沉积法从氯化锌和氯化钾溶液中制得氧化锌纳米棒。将沉积了氧化锌纳米棒的模板固定在打磨后的玻碳电极表面，并将模板溶解。再通过在氧化锌纳米棒修饰电极的表面直接固定乙酰胆碱酯酶，制备出乙酰胆碱酯酶生物传感器。自然晾干后，所得乙酰胆碱酯酶氧化锌生物传感器用于辛硫磷农药的测定。试验结果表明：在含有0．5mmol·L^-1的巯基乙酰胆碱的pH7．38磷酸盐缓冲溶液中，乙酰胆碱酯酶-氧化锌修饰电极的氧化峰电流显著提高，而再向其中加入酶抑制剂辛硫磷后，电流明显减小，在此基础上提出了一种高灵敏度的测定辛硫磷农药的方法。在优化的条件下，辛硫磷浓度在9．85×10^-6～4．95×10^-4mol·L^-1之间，其浓度的对数与抑制率呈线性关系，检出限（3S／N）为5．99×10mol·L^-1。Using gold-sprayed polyearbonate template as working electrode, ZnO nanorods were prepared by electro-deposition from a solution of ZnCl2 and KCl. The template deposited with ZnO nanorods was adhered and dissolved on surface of polished glassy carbon electrode （GCE）. Finally, the acetylcholinesterase （ACHE） biosensor was prepared hy immobilizing the AchE directly onto the surface of the ZnO nanorods modified GCE. After airdrying, the biosensor, AChE-ZnO/GCE, was ready for use in determination of phoxim pesticides. It was found that in the presence of 0. 5 mmol·L^-1 hydrosulfoacetyleholine （ATCh）, the oxidative peak current was remarkable raised at the AChE-ZnO/GCE in PBS of pH 7. 38, but significant lowering of the peak current at the same biosensor, under same condition, was observed when phoxim was added. Linear relationship between the rate of decrease in peak current （I%） and logarithm of concentration of phoxim （a representative object for phoxime pesticides） was found in the range of 9. 85 × 10^-6-4.95 × 10^-4 mol · L^-1 Detection limit （3S/N） of the method found was 5.99×10mol ·L^-1.

关 键 词：乙酰胆碱酯酶 生物传感器 氧化锌纳米棒 辛硫磷 

分 类 号：O657.1[理学—分析化学]