title: Application of a tandem mass spectrometer and core-shell particle column for the determination of 151 pesticides in grains.
abstract: A comparison of ultrahigh performance liquid chromatography (UHPLC) with a 2.6 μm core-shell particle column (Kinetex C(18)) and conventional liquid chromatography (LC) with a 3 μm porous particle column (Atlantis dC(18)), coupled with electrospray ionization tandem mass spectrometry (ESI-MS/MS), for the determination of 151 pesticides in grains is presented in this study. Pesticides were extracted from grain samples using a procedure known as QuEChERS (quick, easy, cheap, effective, rugged, and safe). Quantification, with an analytical range from 5 to 500 μg/kg, was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards. The method performance parameters that included overall recovery, intermediate precision, and measurement uncertainty were evaluated using a designed experiment, that is, the nested design. The UHPLC (Kinetex C(18)) was superior to conventional LC (Atlantis dC(18)) as it yielded a shorter analytical run time, increased method sensitivity, and improved method performance. For UHPLC/ESI-MS/MS (Kinetex C(18)), 90% of the pesticides studied had recoveries between 81 and 110%, 88% of the pesticides had intermediate precision ≤20%, and 84% of the pesticides showed measurement uncertainty ≤40%. As compared to UHPLC/ESI-MS/MS (Kinetex dC(18)), the LC/ESI-MS/MS (Atlantis dC(18)) showed a relatively lower sensitivity, less repeatability, and larger measurement uncertainty. UHPLC/ESI-MS/MS with 2.6 μm core-shell particle column and scheduled MRM proved to be a good choice for quantification or determination of pesticides in grains.
authors.affiliation: Canadian Food Inspection Agency Calgary Laboratory, Calgary, Alberta, Canada. Jian.Wang@inspection.gc.ca
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Willis
authors.initials: W
authors.lastname: Chow
authors.forename: Wendy
authors.initials: W
authors.lastname: Cheung
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D002523:Edible Grain / Q000737:chemistry*; D005506:Food Contamination / Q000032:analysis; D010575:Pesticides / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D010575:Pesticides