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Determination of chlorfenapyr in leek grown under greenhouse conditions with GC-μECD and confirmation by mass spectrometry.

Natural Products Chemistry Laboratory, Division of Applied Bioscience and Biotechnology, College of Agriculture and Life Science, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju 500-757, Republic of Korea.
Biomedical Chromatography (Impact Factor: 1.95). 05/2011; 26(2):172-7. DOI: 10.1002/bmc.1643
Source: PubMed

ABSTRACT A simple analytical method was developed for the determination of chlorfenapyr residues in leeks grown under greenhouse conditions. Residues were extracted by salting out, analyzed by gas chromatography with microelectron-capture detection, and confirmed via gas chromatography-mass spectrometry. The calibration curves were found to be linear with correlation coefficients (r(2) ) in excess of 0.998. The limits of detection and quantification were 0.0015 and 0.005 mg kg(-1) , respectively. For validation purposes, recovery studies were carried out at low and high levels. Yield recovery rates were 87.27-89.64% with a relative standard deviation <6%. A maximum of 0.32 mg kg(-1) of chlorfenapyr residue was detected in leek sample sprayed three times at 7 day intervals until 7 days prior to harvest. The results of this study suggest that chlorfenapyr is acceptable for application in/on leeks under the recommended dosage regimen.

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