吡虫啉分子印迹电化学传感器的制备及电学传感机理分析  

Preparation of imidacloprid imprinted electrochemical sensor and its electrical sensing mechanism

作　　者：郭明[1] 谭贤[1] 梁东军[1] 李铭慧[1] 白丽群[1] 

机构地区：[1]浙江农林大学理学院,浙江临安311300

出　　处：《农药学学报》2014年第5期559-569,共11页Chinese Journal of Pesticide Science

基　　金：国家自然科学基金项目(20877072);浙江省科技厅项目(2010C33070);浙江省自然科学基金项目(LQ12C16002)

摘　　要：以壳聚糖为功能基体、吡虫啉(imidacloprid,IMI)为模板分子、戊二醛为交联剂,应用恒电位沉积法制备了分子印迹电极并构建了吡虫啉印迹传感器(IMI-MIP/F-CNTs/GCE)。利用循环伏安法(cyclic voltammetry,CV)、差分脉冲伏安法(differential pulse voltammetry,DPV)及交流阻抗法(electrochemical impedance spectroscopy,EIS)考察了新型传感器对吡虫啉的检测性能并构建等效电路模型。结果表明:成功制备了新型分子印迹电化学传感器;传感器表观表面积比裸电极显著提高;新型传感器具有良好的印迹效果,相较于其他结构类似的烟碱化合物(如啶虫脒等),IMIMIP/F-CNTs/GCE对吡虫啉表现出高效的选择识别能力,且在cI M I≤1.0×10-6mol/L范围内传感器峰电流与cI M I存在定量关系;数据模拟分析获得传感器电学阻抗谱等效电路模型为R1(C1(R2(CPE2(R3)))),计算等效电路各元件参数证明该模型能有效模拟传感器检测吡虫啉的传感机理。所得结果可为烟碱类农药残留检测提供一种新的分析方法,为农药残留检测传感器分析机理研究提供有益参考。A novel molecularly imprinted membranes electrochemical sensor with good imprinted capacity to imidacloprid （ IMI） was prepare by electrodeposition technique. Chitosan was deposited onto the surface of glassy carbon electrode as a functional monomer along with template molecules acetamiprid and glutaraldehyde as a crosslinking agent. Through cyclic voltammetry （ CV） , differential pulse voltammetry （ DPV） , electrochemical impedance spectroscopy （ EIS） , detection performance of the new sensor on imidacloprid was studied and the equivalent circuit model was constructed. The results showed that the new molecularly imprinted electrochemical sensor was prepared successfully;compared with the bare electrode, the sensor？s apparent surface area was increased significantly; the＆nbsp;imprinted effect of new sensors is good, and compared with other nicotine compound （ e. g. acetamiprid ） with the similar structure, IMI-MIP/F-CNTs/GCE exhibited a high effective and selective recognition ability for imidacloprid, and the quantitative relationship between the peak current of sensor and cIMI was existed at cIMI≤1 ×10 - 6 mol/L; the electrical impedance equivalent circuit model of sensor was R1 （ C1 （ R2 （ CPE2 （ R3 ） ） ） ） though data simulation analysis. The parameters of each element equivalent circuit proved that R1 （ C1 （ R2 （ CPE2 （ R3 ） ） ） ） equivalent circuit can effectively simulate the sensing mechanism of sensor when it detects the imidacloprid. The results of this work could provide a new analysis method of detecting the neonicotinoid pesticide and provide the reference for the detection pesticide mechanism by the sensors.

关 键 词：分子印迹 传感器 吡虫啉 等效电路模型 

分 类 号：Q657.1[生物学—生物物理学] TQ450.26[化学工程—农药化工]