Single-laboratory validation and uncertainty analysis of 82 pesticides determined in pomegranate, apple, and orange by ethyl acetate extraction and liquid chromatography/tandem mass spectrometry

J AOAC Int. 2008 Nov-Dec;91(6):1435-45.

Abstract

Single-laboratory validation results are reported for the multiresidue determination of 82 pesticides at < or = 10 ng/g levels in pomegranate, apple, and orange. Samples were extracted with ethyl acetate, and the extracts were cleaned up by dispersive solid-phase extraction with primary secondary amine sorbent. The concentrations of the pesticides were estimated within 18 min of chromatographic run time by liquid chromatography/mass spectrometry with multiple-reaction monitoring. The method was reproducible (HorRat of < 0.5 at 10 ng/g) with measurement uncertainties of < 15% for all the compounds at 10 nglg in all 3 matrixes. The limits of quantitation ranged from 2.5 to 5.0 ng/g with recoveries of 70-120% for most pesticides. Matrix-induced signal suppressions were significantly higher in orange compared with those in pomegranate and apple. The method offers a less expensive and safer alternative to the existing multiresidue analysis methods for fruits and vegetables.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetates
  • Centrifugation
  • Chromatography, Liquid
  • Citrus sinensis / chemistry*
  • Food Contamination / analysis
  • Lythraceae / chemistry*
  • Malus / chemistry*
  • Pesticide Residues / analysis*
  • Pesticides / analysis*
  • Reference Standards
  • Reproducibility of Results
  • Solvents
  • Spectrometry, Mass, Electrospray Ionization
  • Tandem Mass Spectrometry

Substances

  • Acetates
  • Pesticide Residues
  • Pesticides
  • Solvents
  • ethyl acetate