Isotope-labeled internal standards and grouping scheme for determination of neonicotinoid insecticides and their metabolites in fruits, vegetables and cereals – A compensation of matrix effects. (1st May 2020)

• Record Type: Journal Article
• Authors: Wu, Changcai; Dong, Fengshou; Mei, Xiangdong; Ning, Jun; She, Dongmei
• Is Part Of: Food chemistry. Volume 311(2020)
• Publication Date: 2020-05-01
• Subjects: Neonicotinoid insecticides -- Metabolites -- Isotope-labeled internal standard method -- Matrix effects; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2019.125871
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Method for measuring 8 neonicotinoids and 11 metabolites in 6 matrices. Extract and clean-up were optimized to achieve good recoveries. LC–MS/MS conditions were optimized to analyze 22 compounds in 6 min. Matrix effects were corrected with only three isotope-labeled internal standards. This is the first report on the determination of multiple neonicotinoid metabolites. Abstract: Neonicotinoid insecticides (NIs) are widely used. However they produce high levels of residues and are toxic to non-target organisms, especially when their metabolites exhibit comparable or elevated toxicities. In this study, we established a multi-residue analytical method for analyzing 20 compounds – 8 NIs and their 11 major toxic metabolites. QuEChERS pretreatment and ultra-high-performance liquid chromatography–tandem mass spectrometry were used to detect residues in fruits, vegetables and cereals. Determination time was shortened to 6 min. Average recoveries of all compounds were in the range of 90.1–105.5%, with relative standard deviations lower than 15.0% and the limit of quantitation being 10 µg kg −1 . For the first time, 8 NIs and 11 major toxic metabolites were grouped simultaneously, such that the matrix effect of analytes was satisfactorily corrected using their own isotopically labeled molecules; other NIs and metabolites in the same group were also corrected. This is the first report that simultaneously quantified multiple metabolites of eight NIs in multiple matrices.