Application of Gas Chromatography Coupled to Quadrupole-Orbitrap Mass Spectrometry for Pesticide Residue Analysis in Cereals and Feed Ingredients

A method for residue analysis of pesticides and polychlorinated biphenyls in cereals and feed ingredients based on QuEChERS extraction, programmed temperature vaporizer large-volume injection, and GC with electron ionization (EI) quadrupole Orbitrap full-scan high-resolution MS (60 000 full width at half-maximum at m/z 200) has been developed. In addition to full-scan acquisition, simultaneous full-scan and selected-ion monitoring acquisition was used to improve detectability in incidental cases in which analytes coeluted with intense signals from coextractants. The method was successfully validated down to 10 µg/kg for a single commodity (wheat) using matrix-matched calibration, and for multiple-feed matrixes using standard addition. Identification according to European Union requirements was achieved in >90% of the analyte/matrix combinations, and suggestions for further increasing identification rates have been made. Performance characteristics were compared to an existing method for residue analysis based on GC with EI tandem MS (triple quadrupole).