Abstract: Objective To establish a multi residue liquid chromatography-tandem mass spectrometric（LC-MS/MS） method for the determination of 13 pyridine and pyrimidine herbicides in fruit and vegetable sauce. Methods The samples were extracted with acetonitrile（containing 1% formic acid）,purified using QuEChERS（quick,easy,cheap,effective,rugged and safe） technology,and separated using a ZORBAX SB-Aq column（2.1 mm×150 mm,3.5 μm）. The gradient elution was performed using an acetonitrile 0.1% formic acid aqueous solution（containing 5 mmol/L ammonium acetate） as the mobile phase,and detected using LC-MS/MS in multiple-reaction monitoring（MRM） mode. Quantification was performed using an external standard method. Results 13 pyridine and pyrimidine herbicides showed good linear relationships within their respective concentration ranges,with correlation coefficients greater than 0.999. The average recovery rates for three different concentrations ranged from 80.36% to 118.74%,with relative standard deviations of 0.22% to 9.62%,and the limits of detection was 0.06-1.60 μg/kg. Conclusion The method is simple and sensitive,with good reproducibility,and can be used for simultaneous detection of 13 pyridine and pyrimidine herbicides in fruit and vegetable sauce.

Key words: Liquid chromatography-tandem mass spectrometry, Fruit and vegetable sauce, Pyridine and pyrimidine herbicides