[ Objectives] This study was conducted to establish a QuEChERS-gas chromatography method for determination of eight kinds of organophosphorus pesticide residues in pepper. [Methods] The samples were extracted by aceto...[ Objectives] This study was conducted to establish a QuEChERS-gas chromatography method for determination of eight kinds of organophosphorus pesticide residues in pepper. [Methods] The samples were extracted by acetonitrile, and anhydrous magnesium sulfate was used for salting out. The extracts were then purified by dispersive solid phase extraction combining with GCB, C18 and PSA. Samples were analyzed by FPD detector. External standard was used as quantitive method. [ Results] The detection limits were in the range of 0. 001 -0. 008 mg/kg, the average recoveries ranged from 83.5% to 101.2% , and the relative standard deviation （RSD） of the eight organophosphorus pesticide residues were below 5%. [ Conclusions] The method is simple, quick, easy and effective for the determination of pepper.展开更多
[Objectives] To establish Qu ECh ERS based extraction method for determining multiple pesticide residues in okra combined with programmed temperature vaporizer-gas chromatography-triple quadrupole mass spectrometry( P...[Objectives] To establish Qu ECh ERS based extraction method for determining multiple pesticide residues in okra combined with programmed temperature vaporizer-gas chromatography-triple quadrupole mass spectrometry( PTV-GC-MS/MS) and ultra high performance liquid chromatography-mass spectrometry( UPLC-MS/MS). [Methods] In this experiment,124 pesticide residues in okra were determined by an optimized Qu ECh ERS method combined with PTV-GC-MS/MS and UPLC-MS/MS. The pesticides in okra were extracted and purified by the optimized Qu ECh ERS pretreatment method and determined by PTV-GC-MS/MS and UPLC-MS/MS. [Results] In this experiment,124 kinds of pesticides had a good linearity with a limit of detection( LOD) of 0. 000 5-0. 008 0 mg/kg; the average recovery rate at three levels was 65. 5%-128. 1% with relative standard deviation of 2. 2%-9. 7%. [Conclusions] This method is simple,rapid,accurate and sensitive,and can provide reliable and valid data support for the determination of multiple pesticide residues in okra by GC-MS/MS and UPLC-MS/MS.展开更多
The presence of pesticide residues in food and vegetables is a growing concern for consumers.To monitor these residues reliably,a selective and sensitive multiresidue system has been developed and validated in tomato ...The presence of pesticide residues in food and vegetables is a growing concern for consumers.To monitor these residues reliably,a selective and sensitive multiresidue system has been developed and validated in tomato by gas chromatography–tandem mass spectrometry(GC-MS/MS).Titanium-coated graphite with carbon nanotube(CNT)in acrylonitrile–butadiene–styrene(ABS)used as reversed-dispersive solid-phase extraction materials with modified QuEChERS(Quick,Easy,Cheap,Effective,Rugged,and Safe)method.Titanium-coated graphite with CNT-ABS is synthesized,characterized by X-ray diffraction and scanning electron microscopy.The clean-up performance of titanium-coated graphite with CNT-ABS was demonstrated to be better to primary secondary amine and graphitized carbon black cartridges.The processing of two multiple reaction monitoring transformations for each analyte is done using GC-MS/MS in electron impact mode.Satisfactory purification and recovery effects(74%–100%)of 35 pesticides were achieved in tomato matrices when using 5 mg of titanium-coated graphite ABS-CNT nanocomposite.It was observed that quinolphos and deltamethrin are present above the maximum residue limit.The technique proved to be reliable and sensitive in tomato samples for the routine testing of 35 pesticides.展开更多
目的建立实时直接分析串联质谱法(direct analysis in real time-tandem mass spectrometry,DART-MS/MS)检测茶叶中烯酰吗啉、噻虫嗪、吡唑醚菌酯、吡虫啉、灭多威、吡蚜酮、杀线威、仲丁威、啶虫脒等9种常见农药残留的分析方法。方法...目的建立实时直接分析串联质谱法(direct analysis in real time-tandem mass spectrometry,DART-MS/MS)检测茶叶中烯酰吗啉、噻虫嗪、吡唑醚菌酯、吡虫啉、灭多威、吡蚜酮、杀线威、仲丁威、啶虫脒等9种常见农药残留的分析方法。方法样品采用QuEChERS方法进行前处理,粉碎茶样通过乙腈提取,采用无水MgSO4和NaCl盐析,N-丙基乙二胺(primary secondary amine,PSA)、C18和石墨化碳黑(graphitized carbon black,GCB)分散固相萃取净化,用玻璃棒蘸取上清液经DART-MS/MS检测。结果 9种化合物在0.5~50μg/L范围内线性关系良好,相关系数(r2)均大于0.9,9种农药在5、10和50μg/kg添加水平的平均回收率为70.1%~109.8%,相对标准偏差(relative standar ddeviation,RSD)为15.5%~22.4%,9种农药的定量限均为5μg/kg。结论该方法提取、净化环节简单、快速,无需氮吹转溶;上机检测环节无需色谱分离,直接通过实时直接质谱分析,大大节省了分析时间。该方法的建立为现有茶叶农药残留检测方法和标准提供了一种有益的补充。展开更多
基金Supported by Post-doctoral Scientific Fund of China(No.2017M611382)Autonomy Program of Economy,Trade and Information Commission of Shenzhen Municipality(No.20170427160059840)
文摘[ Objectives] This study was conducted to establish a QuEChERS-gas chromatography method for determination of eight kinds of organophosphorus pesticide residues in pepper. [Methods] The samples were extracted by acetonitrile, and anhydrous magnesium sulfate was used for salting out. The extracts were then purified by dispersive solid phase extraction combining with GCB, C18 and PSA. Samples were analyzed by FPD detector. External standard was used as quantitive method. [ Results] The detection limits were in the range of 0. 001 -0. 008 mg/kg, the average recoveries ranged from 83.5% to 101.2% , and the relative standard deviation （RSD） of the eight organophosphorus pesticide residues were below 5%. [ Conclusions] The method is simple, quick, easy and effective for the determination of pepper.
基金Supported by Science and Technology Planning Project of Guangdong Province(2014A040401008)
文摘[Objectives] To establish Qu ECh ERS based extraction method for determining multiple pesticide residues in okra combined with programmed temperature vaporizer-gas chromatography-triple quadrupole mass spectrometry( PTV-GC-MS/MS) and ultra high performance liquid chromatography-mass spectrometry( UPLC-MS/MS). [Methods] In this experiment,124 pesticide residues in okra were determined by an optimized Qu ECh ERS method combined with PTV-GC-MS/MS and UPLC-MS/MS. The pesticides in okra were extracted and purified by the optimized Qu ECh ERS pretreatment method and determined by PTV-GC-MS/MS and UPLC-MS/MS. [Results] In this experiment,124 kinds of pesticides had a good linearity with a limit of detection( LOD) of 0. 000 5-0. 008 0 mg/kg; the average recovery rate at three levels was 65. 5%-128. 1% with relative standard deviation of 2. 2%-9. 7%. [Conclusions] This method is simple,rapid,accurate and sensitive,and can provide reliable and valid data support for the determination of multiple pesticide residues in okra by GC-MS/MS and UPLC-MS/MS.
文摘The presence of pesticide residues in food and vegetables is a growing concern for consumers.To monitor these residues reliably,a selective and sensitive multiresidue system has been developed and validated in tomato by gas chromatography–tandem mass spectrometry(GC-MS/MS).Titanium-coated graphite with carbon nanotube(CNT)in acrylonitrile–butadiene–styrene(ABS)used as reversed-dispersive solid-phase extraction materials with modified QuEChERS(Quick,Easy,Cheap,Effective,Rugged,and Safe)method.Titanium-coated graphite with CNT-ABS is synthesized,characterized by X-ray diffraction and scanning electron microscopy.The clean-up performance of titanium-coated graphite with CNT-ABS was demonstrated to be better to primary secondary amine and graphitized carbon black cartridges.The processing of two multiple reaction monitoring transformations for each analyte is done using GC-MS/MS in electron impact mode.Satisfactory purification and recovery effects(74%–100%)of 35 pesticides were achieved in tomato matrices when using 5 mg of titanium-coated graphite ABS-CNT nanocomposite.It was observed that quinolphos and deltamethrin are present above the maximum residue limit.The technique proved to be reliable and sensitive in tomato samples for the routine testing of 35 pesticides.
文摘目的建立实时直接分析串联质谱法(direct analysis in real time-tandem mass spectrometry,DART-MS/MS)检测茶叶中烯酰吗啉、噻虫嗪、吡唑醚菌酯、吡虫啉、灭多威、吡蚜酮、杀线威、仲丁威、啶虫脒等9种常见农药残留的分析方法。方法样品采用QuEChERS方法进行前处理,粉碎茶样通过乙腈提取,采用无水MgSO4和NaCl盐析,N-丙基乙二胺(primary secondary amine,PSA)、C18和石墨化碳黑(graphitized carbon black,GCB)分散固相萃取净化,用玻璃棒蘸取上清液经DART-MS/MS检测。结果 9种化合物在0.5~50μg/L范围内线性关系良好,相关系数(r2)均大于0.9,9种农药在5、10和50μg/kg添加水平的平均回收率为70.1%~109.8%,相对标准偏差(relative standar ddeviation,RSD)为15.5%~22.4%,9种农药的定量限均为5μg/kg。结论该方法提取、净化环节简单、快速,无需氮吹转溶;上机检测环节无需色谱分离,直接通过实时直接质谱分析,大大节省了分析时间。该方法的建立为现有茶叶农药残留检测方法和标准提供了一种有益的补充。
