四氟苯菊酯与苯醚氰菊酯的质谱裂解机理研究

Study on Mass Spectrum Fragmentation Mechanism for Transfluthrin and Cyphenothrin

本文利用质谱的高分辨率及高质量准确度的特点,采用气质联用法对四氟苯菊酯和苯醚氰菊酯的质谱裂解机理进行分析研究。结果表明这两种菊酯类农药具有相似的质谱裂解行为:由于羰基上氧原子的电荷诱导作用,发生α断裂得到不稳定的碎片离子,继续失去一个CO,得到稳定的基峰碎片离子。选定这两种杀虫剂痕量检测的定性、定量离子。本实验揭示了拟除虫菊酯类杀虫剂的质谱裂解途径,为此类杀虫剂残留分析时快速筛查、确证提供参考和捷径。

The fragmentation mechanism of transfluthrin and cyphenothrin has been studied with high resolution and high mass accuracy. The results indicated that the two structurally similar pyrethroids have similar fragmentation pathways. On the charge induction of carbonyl oxygen atoms,the chemical bond between the carbonyl and cyclopropane in the molecules is prone to occur fracture, and the unstable resulting fragment ions then losed one CO, and the stable base peak fragment ions were obtained. From these ions, the qualitative and quantitative fragment ions of 2pyrethroid insecticides were selected. This test demonstrated the fragmentation route of pyrethroid insecticides and will be valuable for the rapid screening and identification of such pesticides.