Determination of 31 pesticide residues in Chinese chives by modified QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry

Based on QuEChERS and ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), a method for simultaneous detection of 31 pesticide residues in Chinese chives was established. The Chinese chive samples were extracted by acetonitrile, cleaned-up by modified QuEChERS method and then analyzed by UPLC-MS/MS. Results showed that good linear relationship was obtained between the mass concentrations of 31 pesticides and the corresponding peak areas in the range of 0.5-100 μg/L with all of the correlation coefficients higher than 0.995, and the LOQs (limits of quantification) of the pesticides were all 0.01 mg/kg. The average recoveries of 31 pesticides ranged from 70%-102% at the spiking level of 0.01, 0.1 and 1 mg/kg with RSDs lower than 11% (n = 5). The method was rapid, simple, reliable, efficient, and low cost, and was suitable for simultaneous determination of 31 pesticide multi-residues in Chinese chives.