title: [Determination of glufosinate residue in tea by liquid chromatography-tandem mass spectrometry coupled with precolumn derivatization].
abstract: A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the determination of glufosinate (GLUF) residue in tea. The GLUF was extracted with water for 30 min under ultrasonication, and cleaned-up using a C18 solid phase extraction cartridge, then derived using fluorenylmethylchloroformate (FMOC-Cl) in borate buffer for 2 h. The separation was performed on a Kinetex C18 column with the mobile phases of acetonitrile and 5 mmol/L ammonium acetate aqueous solution (containing 0.2% (v/v) formic acid) in a gradient elution mode. The identification and quantification of the GLUF were carried out by MS/MS in negative electrospray ionization (ESI(-)) and multiple reaction monitoring (MRM) mode, the quantification analysis was performed by external standard method. The calibration curve showed good linearity in the range of 2.5 - 50.0 microg/L with the correlation coefficient r2 > 0.999. The limit of quantification (LOQ) was 0.10 mg/kg. The average recoveries of GLUF spiked at 0.10, 0.50 and 1.00 mg/kg levels in tea were between 61.6% and 81.4%, and the relative standard deviations (RSDs) were between 3.2% and 8.4%. The method is simple, rapid, sensitive, accurate and suitable for the confirmation and quantification of GLUF in tea.
authors.affiliation: Fujian Entry-Exit Inspection and Quarantine Bureau, Fuzhou 350001, China. xmulyh@163.com
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Lin
authors.forename: Zhengcai
authors.initials: Z
authors.lastname: Liu
authors.forename: Fang
authors.initials: F
authors.lastname: Yang
authors.forename: Yuanjin
authors.initials: Y
authors.lastname: Qiu
authors.forename: Suzhen
authors.initials: S
authors.lastname: Liu
authors.forename: Zhijiao
authors.initials: Z
authors.lastname: Su
authors.forename: Qiong
authors.initials: Q
authors.lastname: Zhang
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Xue
authors.forename: Yu
authors.initials: Y
authors.lastname: Fang
mesh_terms: D000613:Aminobutyrates / Q000032:analysis*; D002853:Chromatography, Liquid; D005506:Food Contamination / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D053719:Tandem Mass Spectrometry; D013662:Tea / Q000737:chemistry*
chemical_list: D000613:Aminobutyrates; D010573:Pesticide Residues; D013662:Tea; C003121:phosphinothricin