title: [Determination of 12 azole fungicide residues in beans and corn by offline disperse solid phase extraction and gas chromatography-negative chemical ionization mass spectrometry].
abstract: A confirmatory method is proposed for the determination of 12 azole fungicide residues in beans and corn with the technique of offline disperse solid phase extraction (DSPE) and gas chromatography-negative chemical ionization mass spectrometry (GC-NCI/MS). The pesticides interested were extracted from the samples with acetonitrile containing 1% acetic acid and simultaneous liquid-liquid partitioning formed by adding anhydrous magnesium sulfate plus sodium acetate followed by a simple cleanup step known as dispersive solid-phase extraction. The aliquot was determined and confirmed by GC-NCI/MS using external standard method. The recoveries of all pesticides were between 70% and 130% at the three spiked levels, 10 microg/kg, 20 microg/kg and 40 microg/kg. The relative standard deviations were less than 13.9%. The linearity of method was good from 50 to 1 000 microg/L. The limits of quantification (LOQ) were less than 8 microg/kg. The method is selective with no interference and is suitable for the confirmatory of pesticide residues in beans and corn.
authors.affiliation: Laboratory of Food, Jiangsu Entry-Exit Inspection and Quarantine Bureau, Nanjing 210001, China. swj9722418@yahoo.com.cn
authors.forename: Weijian
authors.initials: W
authors.lastname: Shen
authors.forename: Qianwen
authors.initials: Q
authors.lastname: Gui
authors.forename: Keyao
authors.initials: K
authors.lastname: Yu
authors.forename: Ningning
authors.initials: N
authors.lastname: Sun
authors.forename: Zengyun
authors.initials: Z
authors.lastname: Zhao
authors.forename: Chongyu
authors.initials: C
authors.lastname: Shen
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
authors.forename: Yuan
authors.initials: Y
authors.lastname: Jiang
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Chu
mesh_terms: D001393:Azoles / Q000032:analysis; D007887:Fabaceae / Q000737:chemistry*; D005506:Food Contamination / Q000032:analysis*; D005659:Fungicides, Industrial / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D010573:Pesticide Residues / Q000032:analysis*; D052616:Solid Phase Extraction; D003313:Zea mays / Q000737:chemistry*
chemical_list: D001393:Azoles; D005659:Fungicides, Industrial; D010573:Pesticide Residues