Determination of fenaminstrobin in vegetables by gas chromatography-mass spectrometry with solid phase extraction and its fragmentation mechanism

A solid phase extraction coupled with gas chromatography-mass spectrometric(SPE-GC-MS) method was established for the determination of fenaminstrobin(SYP-1620) residue in vegetables.The target analytes in samples were extracted with ethyl acetate in high-speed homogenate extraction,followed by solid phase extraction clean-up with the mixture of anhydrous magnesium sulphate(MgSO4),silicone gel and graphitized carbon(GCB),analyzed by GC-MS under selected ion monitor mode(SIM) and quantified by matrix-match standard solution in external standard method.Good linear was obtained in the range of 0.02-1.00 mg/L for fenaminstrobin with correlation coefficient not less than 0.999 under the optimum conditions,and the limits of detection(S/N=3) and the limits of quantitation(S/N=10) were 0.006 mg/kg and 0.02 mg/kg,respectively.The average recoveries of fenaminstrobin from blank samples at three spiked levels of 0.02,0.04 and 0.2 mg/kg ranged from 94% to 99% with RSDs of 2.3%-2.9%.The fragmentation mechanism of fenaminstrobin was also studied in this article in which the qualitative ions and quantitative ions were confirmed.