title: [Simultaneous determination of glyphosate and glufosinate-ammonium residues in tea by ultra performance liquid chromatography-tandem mass spectrometry coupled with pre-column derivatization].
abstract: A method was developed for the determination of glyphosate (GLY) and glufosinate-ammonium (GLUF) in tea using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The sample was extracted with ultrapure water and dichloromethane for 30 min under ultrasonication, followed by a simple cleanup with a C18 solid phase extraction (SPE) cartridge, and then GLY and GLUF were derivatized using 9-fluorenylmethoxycarbonyl (FMOC-Cl) in borate buffer for 2 h. The derivatives of GLY and GLUF were separated on a Waters C18 column (50 mm x 2.1 mm, 1.7 μm) in a gradient elution mode, and finally detected with positive electrospray ionization-mass spectrometry (ESI-MS/MS ) in multiple reaction monitoring (MRM) mode. The quantification analysis was performed by external standard method. The method showed a good linearity (r > 0. 990) in the range of 0.003 125-0.1 mg/L. The limits of detection (LODs) of GLY and GLUF were 0.03 mg/kg. At the spiked levels of 0.375, 1.5 and 4.5 mg/kg, the recoveries of GLY and GLUF were 87.37%-99.11% and 81.44% -86.17% respectively, and the relative standard deviations (RSDs) (n = 6) of GLY and GLUF were 0.68%-1.35% and 1.01%-2.33%, respectively. This method is simple, rapid and characterized with acceptable sensitivity and accuracy to meet the requirements for the analysis of GLY and GLUF simultaneously in tea.
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Wu
authors.forename: Xiaoquan
authors.initials: X
authors.lastname: Chen
authors.forename: Haijun
authors.initials: H
authors.lastname: Xiao
authors.forename: Binqiu
authors.initials: B
authors.lastname: Liu
mesh_terms: D000613:Aminobutyrates / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005506:Food Contamination; D005998:Glycine / Q000031:analogs & derivatives* / Q000032:analysis; D010573:Pesticide Residues / Q000032:analysis*; D053719:Tandem Mass Spectrometry; D013662:Tea / Q000737:chemistry*; D000097797:Glyphosate
chemical_list: D000613:Aminobutyrates; D005998:Glycine; D010573:Pesticide Residues; D013662:Tea; D000097797:Glyphosate; C003121:phosphinothricin