title: Simultaneous determination of 70 pesticide residues in leek, leaf lettuce and garland chrysanthemum using modified QuEChERS method with multi-walled carbon nanotubes as reversed-dispersive solid-phase extraction materials.
abstract: Leek, leaf lettuce and garland chrysanthemum are troublesome vegetables containing large amount of pigments which may bring serious matrix interferences in mass spectrometry analysis. Multi-walled carbon nanotubes (MWCNTs) have a good effect for the cleanup of troublesome matrix. So the study was designed to develop a multi-residue method for the determination of 70 pesticide residues in leek, leaf lettuce and garland chrysanthemum based on a modified QuEChERS procedure using MWCNTs as reversed-dispersive solid phase extraction (r-DSPE) materials to remove the interferences of pigments. PSA and GCB were used as comparison. LC-MS/MS was used to identify and quantify the residue levels of multi-pesticides. The clean-up performance of MWCNTs was demonstrated to be obviously superior to GCB and PSA. This method was validated on leek, leaf lettuce and garland chrysanthemum spiked at the concentration of 10, 50 and 100μgkg(-1) with five replicates. The recoveries of 70 pesticides ranged from 74% to 119%, with relative standard deviations (RSDs) lower than 14.2%. Good linearity (R(2)≥0.9903) was obtained at the range of 10-1000μg/L for all pesticides in the selected matrices. The limit of quantification (LOQs) and limit of detection (LODs) of the 70 pesticides for the selected matrices ranged from 0.3 to 7.9μgkg(-1) and from 0.1 to 2.4μgkg(-1) respectively. The method was successfully applied to the routine monitoring of pesticide residues in market samples.
authors.affiliation: Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Yongtao
authors.initials: Y
authors.lastname: Han
authors.affiliation: Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zou
authors.affiliation: Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Le
authors.initials: L
authors.lastname: Song
authors.affiliation: Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Yanjie
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Qin
authors.affiliation: Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Shaowen
authors.initials: S
authors.lastname: Liu
authors.affiliation: Institute of Pesticide and Environmental Toxicology, Guangxi University, Nanning 530005, PR China.
authors.forename: Xuesheng
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, PR China; Institute of Pesticide and Environmental Toxicology, Guangxi University, Nanning 530005, PR China. Electronic address: canpingp@cau.edu.cn.
authors.forename: Canping
authors.initials: C
authors.lastname: Pan
mesh_terms: D019659:Asteraceae / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000379:methods; D057230:Limit of Detection; D016014:Linear Models; D037742:Nanotubes, Carbon / Q000737:chemistry*; D019697:Onions / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis*; D015203:Reproducibility of Results; D052616:Solid Phase Extraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods; D014675:Vegetables / Q000737:chemistry*
chemical_list: D037742:Nanotubes, Carbon; D010573:Pesticide Residues
keywords: LC–MS/MS; MWCNTs; Pesticide residues; QuEChERS; r-DSPE