电化学方法对农药啶虫脒的间接测定  

Indirect Determination of Acetamiprid by the Electrochemical Method

作　　者：杜诗[1] 金根娣[1] 胡效亚[1] 

机构地区：[1]扬州大学化学化工学院,江苏扬州225002

出　　处：《分析测试学报》2010年第4期331-335,共5页Journal of Instrumental Analysis

基　　金：国家自然科学基金资助项目(20875081;20675071)

摘　　要：啶虫脒本身不具有电化学性质，而其在NaOH溶液中的水解产物为电活性物质。采用循环伏安法（CV）、示差脉冲伏安法（DPV）研究了啶虫脒水解产物在碳糊电极上的电化学行为，并初步探讨了其反应机理。在pH9．0的磷酸盐缓冲液（PBS）中，啶虫脒水解产物在约0．9V（vs．SCE）产生一灵敏的氧化峰，表明电极反应是受扩散控制的不可逆氧化过程。基于啶虫脒水解产物的氧化行为，以0．9V为工作电位，采用计时安培法进行测定，其响应电流与啶虫脒的浓度在2．0×10^-7-2．8×10^-5mol／L范围内呈良好的线性关系，方法的检出限为1．0×10^-7mol／L。该方法成本低、操作方便、重复性好，对人体与环境无毒害，将其用于啶虫脒实际样品的测定，结果满意。The electrochemical behaviors of acetamiprid were investigated by cyclic vohammetric （CV） and differential pulse vohammetric （DPV） method at the carbon paste electrode after it was hydrolyzed in sodium hydroxide. The result indicated that, in pH 9.0 phosphate buffer solution（PBS） the hydrolysate could yield an oxidation peak apparently at the potential of about 0. 9 V （vs. SCE）. And the electrode reaction was an diffusion controlled irreversible oxidation process. Based on its electrochemical behavior, an indirect electrochemical method for the determination of acetamiprid was established. The amperometric response at the working potential of 0.9 V to the concentration of acetamiprid had a linear relationship in the range of 2.0 × 10^-7 - 2. 8×10^-5 mol/L with a correlation co- efficient of 0. 999 7, and the detection limit was 1.0 × 10^ -7 mol/L. The reaction mechanism was aslo discussed. The proposed method was simple, sensitive, and had no harm to human and environment. It was applied in the determination of acetamiprid in real samples with satisfactory result.

关 键 词：啶虫脒 电化学测定 碳糊电极 

分 类 号：O657.1[理学—分析化学] F767.2[理学—化学]