Department of Analytical Chemistry, Fraunhofer Institute of Toxicology and Aerosol Research, Nikolai-Fuchs-Strasse 1, D-30625, Hannover, Germany.
J Am Soc Mass Spectrom. 1994 Jul;5(7):655-75. doi: 10.1016/1044-0305(94)85007-0.
A series of nitrogen- and phosphorus-containing pesticides (amines, anilides, carbamates, phosphonates, phenylureas, sulfonylureas, and triazines) was examined by thermospray (TSP) ionization. A method is described that employs off-line and on-line solid-phase extraction and TSP liquid chromatography-mass spectrometry (LC-MS) with time-scheduled selected ion monitoring (SIM) for environmental monitoring of these pesticides in aqueous samples. SIM detection limits for the pesticides analyzed in conjunction with reversed-phase high-performance liquid chromatography range from 40 to 600 pg. In addition, methods for inducing fragmentation in thermospray LC-MS are presented. The structural information gained therefrom can be used to confirm a tentative identification. Therefore, fragmentation pathways under certain experimental conditions were investigated. Atmospheric pressure chemical ionization, electrospray, fast-atom bombardment, (252)Cf plasma desorption, and collision-activated dissociation spectra are presented for several pesticides to confirm the proposed pathways and to gain additional and complementary information. Further confirmation may be achieved by postcolumn addition of different alkylated amines to the carrier stream in the TSP operation to induce postcolumn on-line derivatization (POD) reactions in the condensed phase of the vaporizer probe with selected pesticides. Additional clustering reactions in combination with solvent-mediated chemical ionization are observed by the POD technique. Both processes can be used to enhance the structural information from TSP spectra and thus the specificity of the method.
一系列含氮和磷的农药（胺类、酰胺类、氨基甲酸酯类、膦酸酯类、苯基脲类、磺酰脲类和三嗪类）通过热喷雾（TSP）离子化进行了检查。本文描述了一种方法，该方法采用离线和在线固相萃取和 TSP 液相色谱-质谱（LC-MS）与定时选择离子监测（SIM），用于环境水样中这些农药的监测。与反相高效液相色谱法相结合分析的农药的 SIM 检测限范围为 40 至 600 pg。此外，还介绍了在热喷雾 LC-MS 中诱导碎裂的方法。从中获得的结构信息可用于确认暂定鉴定。因此，在某些实验条件下研究了碎裂途径。为了确认所提出的途径并获得更多的补充信息，本文还提供了几种农药的大气压化学电离、电喷雾、快原子轰击、（252）Cf 等离子体解吸和碰撞激活解离谱。通过在 TSP 操作中将不同的烷基化胺添加到载流中，可以进一步确认，以诱导在汽化探针的凝聚相中进行柱后在线衍生化（POD）反应，从而选择一些农药。通过 POD 技术观察到与溶剂介导的化学电离相结合的额外聚类反应。这两个过程都可以用于增强 TSP 光谱的结构信息，从而提高方法的特异性。
