Determination of Xinjunan pesticide residue in foodstuffs of plant origin by a modified QuEChERS method and ultra performance liquid chromatography-tandem mass spectrometry

Abstract In this study, the determination of Xinjunan pesticide residue in apple, cottonseed, pepper, tomato, grape and pear by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was established. The samples were purified by a modified QuEChERS method. The analysis was performed by UPLC-MS/MS in multiple reaction monitoring (MRM) mode. Acetonitrile and 1.0 mmol L−1 ammonium acetate (containing 0.1% formic acid) were used as the mobile phases. The external standard method was used for quantification. The average recoveries were 75.6–106.2% with an RSD ≤8.8%. The limits of quantification (LOQs) were 2.0 μg/kg for apple, pepper, tomato, grape and pear and 10.0 μg/kg for cottonseed. The proposed method is fast, sensitive, simple, and accurate and could be used for the quantification of Xinjunan pesticide residue in foodstuffs of plant origin.