A rapid and easy multiresidue method for the determination of pesticide residues in vegetables, fruits, and cereals using liquid Chromatography/tandem mass spectrometry.

Osaka Prefectural Institute of Public Health, Division of Food Chemistry, Nakamichi 1-3-69, Higashinari-ku, Osaka 537-0025, Japan.
Journal of AOAC International (Impact Factor: 1.23). 01/2008; 91(4):871-83.
Source: PubMed

ABSTRACT The applicability of a rapid and easy multiresidue method for determination of pesticide residues in agricultural products by using liquid chromatography/tandem mass spectrometry (LC/MS/MS) was examined. Pesticide residues were extracted with acetonitrile in a disposable tube using a homogenizer, followed by salting out with anhydrous magnesium sulfate and sodium chloride. The extract was purified with a double-layered cartridge column (graphite carbon black/primary-secondary amine silica gel). After removal of the solvent, the extract was resolved in methanol-water and analyzed with LC/MS/MS. Recovery tests of 99 pesticide residues from 7 agricultural products were performed at 20 and 100 ng/g. Throughout all of the agricultural products tested, 47 pesticides exhibited satisfactory recoveries (70-120%) and relative standard deviations (<20%) at both concentrations. The time for processing of 12 samples to test solutions was approximately 2-3 h. This method could be useful for determination of pesticide residues in agricultural products.

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