Abstract A new flow injection analysis method with spectro-electrochemical detection (FIA/SEC) to determine trace levels of imazapyr on water samples is presented. The non-chromatographic method involves the use of a bench photometer, a single-potential potentiostat, a low pressure pumping system and a home-made spectro-electrochemical flow detector (SEC-FD), specifically adapted for the described method and using a stainless steel/electrolytic lead/lead chloride (SS/e-Pb/PbCl2) working electrode. The limit of quantification (LOQ) reached for the optimized work parameters was 0.02 µg/mL, the relative standard deviation (RSD) in the whole range of linear response was less than 2% and a wide linear response range from 0.005 to 6.0 µg/mL was obtained. A standard addition method was used to determine the imazapyr amount in natural waters containing commercial formulation of such herbicide, the Recovery % has values close to 105%. The method performance makes it suitable to analyze the legal imazapyr tolerances established by the U.S. EPA avoiding the use of expensive chromatographic equipments and/or complicated sample preparations.

中文翻译：

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通过增强电化学极化的紫外检测测定痕量灭草烟的廉价 FIA 方法

摘要 提出了一种采用光谱电化学检测 (FIA/SEC) 的流动注射分析新方法，用于测定水样中痕量的灭草烟。非色谱方法涉及使用台式光度计、单电位恒电位仪、低压泵系统和自制光谱电化学流量检测器 (SEC-FD)，特别适用于所述方法并使用不锈钢钢/电解铅/氯化铅（SS/e-Pb/PbCl2）工作电极。优化工作参数的定量限 (LOQ) 为 0.02 µg/mL，整个线性响应范围内的相对标准偏差 (RSD) 小于 2%，线性响应范围为 0.005 至 6.0 µg/得到毫升。使用标准添加方法测定含有此类除草剂的商业制剂的天然水中灭草烟的量，回收率％具有接近105％的值。该方法的性能使其适用于分析美国 EPA 规定的合法灭草烟允许量，避免使用昂贵的色谱设备和/或复杂的样品制备。