Determination of 135 pesticides and their metabolites in Angelica sinensis by ultra-fast liquid chromatography-tandem mass spectrometry coupled with solid-phase extraction

Abstract

A method using solid-phase extraction (SPE) followed by ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) has been established for simultaneously quantitative determination of 135 pesticides and their metabolites (organophosphorus pesticides, pyrethroid pesticides and carbamate pesticides, etc.) in Angelica sinensis. The pesticide residues were extracted from the samples by acetonitrile, cleaned-up with a primary secondary amine (PSA) column and then analyzed using UFLC-MS/MS in multiple reaction monitoring (MRM) mode with positive electrospray ionization. The pesticide residues were quantified by matrix matched standard solution-internal standard method. All of the pesticides had good linear responses with r > 0.99. The average recoveries of the pesticides at the spiked levels of 10, 50, 100 μg/kg ranged from 71.3% - 119.7% with the RSDs of 1.0% - 19.9%, except for clethodim (62.0% - 68.2%). The limits of quantification of the 135 pesticides and their metabolites were 1.0-10.0 μg/kg. The results demonstrated that the method is simple, fast, sensitive and can be used for the analysis of the multiclass of pesticide residues in Angelica sinensis.