BIOMEDICAL CHROMATOGRAPHY, cilt.27, sa.7, ss.924-930, 2013 (SCI-Expanded)
Alachlor residues were determined in pepper and pepper leaf, after 49 days of manufacturer-recommended single- and double-dose application to the soil and plant. The samples were extracted with acetonitrile, partitioned with n-hexane, and purified through solid-phase extraction, and finally detected with a gas chromatography-microelectron capture detector. The linearity of the analytical response across the studied range of concentrations (0.05-4.0 mu g/mL) was excellent, obtaining coefficients of determination (r2) of 0.999. Recovery studies were carried out on spiked pepper and pepper leaf samples, at two concentrations levels (0.2 and 1.0 mg/kg), with three replicates performed at each level. Mean recoveries of 73.1-109.0% with relative standard deviations of 1.3-2.3% were obtained. The method was successfully applied to field samples, and alachlor residue was found in pepper (0.02 mg/kg) and pepper leaf (0.03 mg/kg), at levels lower than the maximum residue limits (0.2 mg/kg) set by the Korea Food and Drug Administration. The field-detected residues were further confirmed with gas chromatography-mass spectrometry with the help of pepper leaf matrix protection. Copyright (c) 2013 John Wiley & Sons, Ltd.