Wang N, Budde W L
Oak Ridge Institute for Science and Education, Cincinnati, Ohio 45268, USA.
Anal Chem. 2001 Mar 1;73(5):997-1006. doi: 10.1021/ac0010734.
Microbore liquid chromatography and positive ion electrospray mass spectrometry are applied to the determination of 16 carbamate, urea, and thiourea pesticides and herbicides in water. The electrospray mass spectra of the analytes were measured and are discussed and mobile-phase matrix effects were evaluated. Analyte positive ion abundances are generally inversely related to the concentration of acetic acid in the acetonitrile-water mobile phase in the range of 0.001-0.1% (v/v) acetic acid. Using an internal standard for quantitative analyses and no acid in the mobile phase, retention time precision, peak width precision, concentration measurement precision, mean recoveries, and instrument detection limits were determined in reagent water. The 16 analytes were also measured in fortified environmental water samples from a recreational lake, a groundwater well, a cistern, a farm pond, and drinking water. These measurements were at 5 ng/mL of each analyte, which is within the range expected for environmental pesticide and herbicide contaminants. The analytes were separated from the environmental water matrixes with an on-line extraction and concentration to provide rapid sample analyses without a slow off-line liquid-liquid or liquid-solid-liquid extraction and extract concentration. Recoveries of 12 of the analytes from 4 environmental water samples were in the range of 75-124% with relative standard deviations in the range of 11-16%.
采用微径液相色谱和正离子电喷雾质谱法测定水中的16种氨基甲酸酯类、脲类和硫脲类农药及除草剂。测定并讨论了分析物的电喷雾质谱图，评估了流动相基质效应。在0.001 - 0.1%（v/v）乙酸的乙腈 - 水流动相范围内，分析物的正离子丰度通常与乙酸浓度呈负相关。使用内标进行定量分析且流动相中不添加酸，在试剂水中测定了保留时间精密度、峰宽精密度、浓度测量精密度、平均回收率和仪器检测限。还对来自休闲湖泊、地下水井、蓄水池、农场池塘和饮用水的加标环境水样中的16种分析物进行了测定。这些测量是在每种分析物浓度为5 ng/mL的条件下进行的，该浓度在环境中农药和除草剂污染物预期范围内。通过在线萃取和浓缩将分析物与环境水基质分离，无需耗时的离线液 - 液或液 - 固 - 液萃取及萃取浓缩，即可实现快速样品分析。从4个环境水样中回收的12种分析物的回收率在75 - 124%范围内，相对标准偏差在11 - 16%范围内。
