Determination of Phoxim Residues in Grains by High Performance Liquid Chromatography-Tandem Mass Spectrometry
A method was developed for the determination of phoxim residues in grains by high performance liquid chromatography-tandem mass spectrometry.The samples were extracted with ethyl acetate,purified by dispersive solid phase extraction with primary secondary amine(PSA),and separated on Agilent Zorbax SB-C18 column with gradient eluted using methanol and 5 mmol/L ammonium acetate solution(containing 0.1％(V/V)formic acid)as mobile phases.The target compound was detected by electrospray ionization(ESI)positive mode under multiple reaction monitoring modes and quantified by external standard method.The linear range for the compound ranged from 5.0 μg/L to 250.0 μg/L,and the correlation coefficient(r2)was 0.9998.The limit of detection(LOD)and limit of quantitation(LOQ)were 0.5 μg/kg and 2.0 μg/kg.At the spiked levels of 2.0,10.0,20.0 μg/kg,the recoveries ranged from 82.2％to 88.9％and the relative standard deviations(RSD)were between 4.6％and 9.3％.The method with good reproducibility and high sensitivity,is simple,rapid,and suitable for the determination of phoxim residues in grains.
High performance liquid chromatography-tandem mass spectrometryGrainsPhoxim
万方数据
维普
