title: Determination of alachlor residues in pepper and pepper leaf using gas chromatography and confirmed via mass spectrometry with matrix protection.
abstract: 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 µg/mL) was excellent, obtaining coefficients of determination (r(2) ) 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.
authors.affiliation: Natural Products Chemistry Laboratory, Biotechnology Research Institute, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757, Republic of Korea.
authors.forename: Md Musfiqur
authors.initials: MM
authors.lastname: Rahman
authors.forename: Hiron Moy
authors.initials: HM
authors.lastname: Sharma
authors.forename: Jong-Hyouk
authors.initials: JH
authors.lastname: Park
authors.forename: A M
authors.initials: AM
authors.lastname: Abd El-Aty
authors.forename: Jeong-Heui
authors.initials: JH
authors.lastname: Choi
authors.forename: Nilufar
authors.initials: N
authors.lastname: Nahar
authors.forename: Jae-Han
authors.initials: JH
authors.lastname: Shim
mesh_terms: D000081:Acetamides / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D002212:Capsicum / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D057230:Limit of Detection; D010573:Pesticide Residues / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D018515:Plant Leaves / Q000737:chemistry*; D015203:Reproducibility of Results
chemical_list: D000081:Acetamides; D010573:Pesticide Residues; C000188:alachlor