Chiral Resolution of Five Enantiomers of Chiral Pesticides in Two Leaf Vegetables by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry with Chiral Stationary Phase

KeyWord:chiral resolution  ultra high liquid chromatography-tandem mass spectrometry  enantiomers  vegetables

Abstract:

      A method based on ultra performance liquid chromatography-tandem mass spectrometry with chiral stationary phase was developed for the simultaneous analysis of five chiral pesticide residues(paclobutrazo,myclobutanil,metalaxyl,triazolone and famoxadone) in leafy vegetables,including Chinese flowering cabbage and leaf lettuce.The sample was extracted with acetonitrile,then purified with primary secondary amine and graphitized carbon black.The upper clear liquid was filtered after centrifugation.After separated with a CHIRRALCEL OD-RH chiral column,the extract was detected using UPLC-MS/MS.Results indicated that the calibration curves of the five chiral pesticides showed good linear relationships in the concentration range of 0.005-1.0 mg¡¤L-1.The recoveries at three spiked levels of 0.01,0.1,0.5 mg¡¤kg-1 were in the range of 68.8%-104% with relative standard deviations of 1.0%-13.7%. This method is rapid,convenient and reliable,and could meet the requirements for residue analysis,and could provide a technical support for the investigation on five chiral pesticides residues in vegetables and their digestion regularity.