Enhanced LC-MS/MS for the quantitation and identification of pesticides in food samples

ANDRÉ SCHREIBER*, REBECCA WITTRIG
*Corresponding author
AB SCIEX, 71 Four Valley Drive, Concord, Ontario, L4K 4V8, Canada

Abstract

This paper describes an analytical workflow to quickly screen food samples for ~280 pesticides. QuEChERS (Quick,Easy, Cheap, Effective, Rugged, and Safe) extracts were diluted and injected directly into a Liquid Chromatography tandemMass Spectrometry system. The quick and easy protocol enabled extraction with high recovery and good reproducibility. For theLC separation, a polar embedded C18 phase was used because of good resolution and excellent peak shape for all targetpesticides. Highly selective and sensitive MS/MS detection was used to quantify pesticides down to the required maximumresidue level of 10ppb, and compounds were identified with high confidence using an ion ratio calculation and mass spectrallibrary searching. The pesticide panel of the described method can easily be extended and customized to match thelaboratory’s need.


...