101
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Fan H, Smuts J, Walsh P, Harrison D, Schug KA. Gas chromatography–vacuum ultraviolet spectroscopy for multiclass pesticide identification. J Chromatogr A 2015; 1389:120-7. [DOI: 10.1016/j.chroma.2015.02.035] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 02/10/2015] [Accepted: 02/11/2015] [Indexed: 11/16/2022]
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102
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Multiresidue analysis of over 200 pesticides in cereals using a QuEChERS and gas chromatography–tandem mass spectrometry-based method. Food Chem 2015; 169:372-80. [DOI: 10.1016/j.foodchem.2014.07.102] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 07/18/2014] [Accepted: 07/21/2014] [Indexed: 11/18/2022]
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103
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Donkor A, Osei-Fosu P, Nyarko S, Kingsford-Adaboh R, Dubey B, Asante I. Validation of QuEChERS method for the determination of 36 pesticide residues in fruits and vegetables from Ghana, using gas chromatography with electron capture and pulsed flame photometric detectors. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2015; 50:560-70. [PMID: 26065516 DOI: 10.1080/03601234.2015.1028833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this study, "Quick, Easy, Cheap, Effective, Rugged and Safe" 'QuEChERS' method was modified for the determination of 36 pesticides fortified at (0.01-1.0) mg kg(-1) in three vegetables and a fruit (lettuce, carrot, tomatoes and pineapples respectively) from Ghana. The method involved extraction with acetonitrile, phase separation with primary secondary amine and magnesium sulfate; the final injection solution was reconstituted in ethyl acetate. Organochlorine and synthetic pyrethroids residues were detected with electron capture detector whereas organophosphorus, pulsed flame photometric detector was used. The recoveries at different concentration levels (0.01, 0.1 and 1.0 mg kg(-1)) were in the range of 83% and 93% with relative standard deviation ranging from 2% to 10% (n = 5) and the coefficient of determination (R(2)) was greater than 0.99 for all the 36 pesticides. The method was successfully tested on 120 real samples from Accra markets and this proved to be useful for monitoring purposes particularly in laboratories that have no gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry.
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Affiliation(s)
- Augustine Donkor
- a Department of Chemistry, University of Ghana , Legon , Accra , Ghana
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104
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Pesticide residues in cashew apple, guava, kaki and peach: GC–μECD, GC–FPD and LC–MS/MS multiresidue method validation, analysis and cumulative acute risk assessment. Food Chem 2014; 164:195-204. [DOI: 10.1016/j.foodchem.2014.05.030] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 05/06/2014] [Accepted: 05/11/2014] [Indexed: 11/20/2022]
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105
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Yang F, Bian Z, Chen X, Liu S, Liu Y, Tang G. Analysis of 118 pesticides in tobacco after extraction with the modified QuEChRS method by LC-MS-MS. J Chromatogr Sci 2014; 52:788-92. [PMID: 23888004 DOI: 10.1093/chromsci/bmt112] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
A liquid chromatography-tandem quadrupole mass spectrometry (LC-MS-MS) multi-residue method for the simultaneous target analysis of a wide range of pesticides in tobacco has been developed. Gradient elution has been used in conjunction with positive mode electrospray ionization tandem mass spectrometry to detect up to 118 pesticides in tobacco. The recoveries obtained for each pesticide ranged between 70 and 118% at two spiked concentration levels. Good linear relationships were observed with correlation coefficients r(2) > 0.992 for all analytes. The established method was successfully applied to the determination of pesticide residues in real tobacco samples in order to validate the suitability for routine analysis.
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Affiliation(s)
- Fei Yang
- China National Tobacco Quality Supervision & Test Center, Zhengzhou 450000, PR China
| | - Zhaoyang Bian
- China National Tobacco Quality Supervision & Test Center, Zhengzhou 450000, PR China No.2, Fengyang Street, Zhengzhou New & Hi-Tech Industries Development Zone, Henan, China
| | - Xiaoshui Chen
- China National Tobacco Quality Supervision & Test Center, Zhengzhou 450000, PR China
| | - Sansan Liu
- China National Tobacco Quality Supervision & Test Center, Zhengzhou 450000, PR China
| | - Yang Liu
- China National Tobacco Quality Supervision & Test Center, Zhengzhou 450000, PR China
| | - Gangling Tang
- China National Tobacco Quality Supervision & Test Center, Zhengzhou 450000, PR China
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106
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Ai G, Sun T, Dong X. Gas chromatography/isotope ratio mass spectrometry: analysis of methanol, ethanol and acetic acid by direct injection of aqueous alcoholic and acetic acid samples. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2014; 28:1674-1682. [PMID: 24975247 DOI: 10.1002/rcm.6948] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/07/2014] [Accepted: 05/14/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Methanol, ethanol, and acetic acid are not easily extracted from aqueous samples and are susceptible to isotope fractionation in gas chromatography/isotope ratio mass spectrometry (GC/IRMS) analysis. Developing a direct dilution GC/IRMS method for aqueous samples, by adjusting the sample concentrations in common solvents to be similar to each other and using a fixed GC split ratio, is very convenient and important because any linearity effects caused by amount-dependent isotope fractionation can be avoided. METHODS The suitability of acetonitrile and acetone solvents for the GC/IRMS analysis of pure methanol, ethanol and acetic acid, and commercial liquor and vinegar samples was evaluated using n-hexane and water as control solvents. All the solvents including water were separated from the analyte on a HP-INNOWAX column and were diverted away from the combustion interface. The influence of liquor matrix on the ethanol GC/IRMS analyses was evaluated by adding pure ethanol to liquor samples. RESULTS Acetonitrile and acetone gave similar δ(13) C values for pure ethanol and pure acetic acid to those obtained in water and n-hexane, and also gave similar δ(13) C values of ethanol in liquor and acetic acid in white vinegar to that obtained in water. For methanol analysis, acetonitrile and refined acetone gave similar δ(13) C values to that obtained in water, but n-hexane was not a suitable solvent. In addition, isotopic fractionation caused by solvent and solute interactions was observed. CONCLUSIONS We recommend using acetonitrile for the GC/IRMS analysis of aqueous alcoholic samples, and acetone for the analysis of aqueous acetic acid samples. This direct dilution method can provide high accurate and precise GC/IRMS analysis of the relative changes in δ(13) C values of methanol, ethanol, and acetic acid.
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Affiliation(s)
- Guomin Ai
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing, 100101, China
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107
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Schug KA, Sawicki I, Carlton DD, Fan H, McNair HM, Nimmo JP, Kroll P, Smuts J, Walsh P, Harrison D. Vacuum Ultraviolet Detector for Gas Chromatography. Anal Chem 2014; 86:8329-35. [DOI: 10.1021/ac5018343] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Kevin A. Schug
- Department of Chemistry & Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Box 19065, Arlington, Texas 76019, United States
| | - Ian Sawicki
- Department of Chemistry & Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Box 19065, Arlington, Texas 76019, United States
| | - Doug D. Carlton
- Department of Chemistry & Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Box 19065, Arlington, Texas 76019, United States
| | - Hui Fan
- Department of Chemistry & Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Box 19065, Arlington, Texas 76019, United States
| | - Harold M. McNair
- Department
of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - John P. Nimmo
- Department of Chemistry & Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Box 19065, Arlington, Texas 76019, United States
| | - Peter Kroll
- Department of Chemistry & Biochemistry, The University of Texas at Arlington, 700 Planetarium Place, Box 19065, Arlington, Texas 76019, United States
| | | | - Phillip Walsh
- VUV Analytics, Inc., Austin, Texas 78717, United States
| | - Dale Harrison
- VUV Analytics, Inc., Austin, Texas 78717, United States
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108
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Portolés T, Mol J, Sancho J, López FJ, Hernández F. Validation of a qualitative screening method for pesticides in fruits and vegetables by gas chromatography quadrupole-time of flight mass spectrometry with atmospheric pressure chemical ionization. Anal Chim Acta 2014; 838:76-85. [DOI: 10.1016/j.aca.2014.06.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 06/05/2014] [Accepted: 06/06/2014] [Indexed: 10/25/2022]
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109
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Morais EHDC, Rodrigues AAZ, Queiroz MELRD, Neves AA, Morais PHD. Determination of thiamethoxam, triadimenol and deltamethrin in pineapple using SLE-LTP extraction and gas chromatography. Food Control 2014. [DOI: 10.1016/j.foodcont.2014.01.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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110
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Khan ZS, Ghosh RK, Girame R, Utture SC, Gadgil M, Banerjee K, Reddy DD, Johnson N. Optimization of a sample preparation method for multiresidue analysis of pesticides in tobacco by single and multi-dimensional gas chromatography-mass spectrometry. J Chromatogr A 2014; 1343:200-6. [PMID: 24746872 DOI: 10.1016/j.chroma.2014.03.080] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 03/22/2014] [Accepted: 03/30/2014] [Indexed: 11/21/2022]
Abstract
A selective and sensitive multiresidue analysis method, comprising 4 7pesticides, was developed and validated in tobacco matrix. The optimized sample preparation procedure in combination with gas chromatography mass spectrometry in selected-ion-monitoring (GC-MS/SIM) mode offered limits of detection (LOD) and quantification (LOQ) in the range of 3-5 and 7.5-15ng/g, respectively, with recoveries between 70 and 119% at 50-100ng/g fortifications. In comparison to the modified QuEChERS (Quick-Easy-Cheap-Effective-Rugged-Safe method: 2g tobacco+10ml water+10ml acetonitrile, 30min vortexing, followed by dispersive solid phase extraction cleanup), the method performed better in minimizing matrix co-extractives e.g. nicotine and megastigmatrienone. Ambiguity in analysis due to co-elution of target analytes (e.g. transfluthrin-heptachlor) and with matrix co-extractives (e.g. δ-HCH-neophytadiene, 2,4-DDE-linolenic acid) could be resolved by selective multi-dimensional (MD)GC heart-cuts. The method holds promise in routine analysis owing to noticeable efficiency of 27 samples/person/day.
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Affiliation(s)
- Zareen S Khan
- National Referral Laboratory, National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India
| | - Rakesh Kumar Ghosh
- Central Tobacco Research Institute, Rajahmundry, Andhra Pradesh 533105, India
| | - Rushali Girame
- National Referral Laboratory, National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India
| | - Sagar C Utture
- National Referral Laboratory, National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India
| | - Manasi Gadgil
- National Referral Laboratory, National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India
| | - Kaushik Banerjee
- National Referral Laboratory, National Research Centre for Grapes, P.O. Manjri Farm, Pune 412 307, India.
| | - D Damodar Reddy
- Central Tobacco Research Institute, Rajahmundry, Andhra Pradesh 533105, India
| | - Nalli Johnson
- Central Tobacco Research Institute, Rajahmundry, Andhra Pradesh 533105, India
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111
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Cervera MI, Portolés T, López FJ, Beltrán J, Hernández F. Screening and quantification of pesticide residues in fruits and vegetables making use of gas chromatography-quadrupole time-of-flight mass spectrometry with atmospheric pressure chemical ionization. Anal Bioanal Chem 2014; 406:6843-55. [PMID: 24828980 DOI: 10.1007/s00216-014-7853-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 04/17/2014] [Accepted: 04/23/2014] [Indexed: 11/27/2022]
Abstract
An atmospheric pressure chemical ionization source has been used to enhance the potential of gas chromatography coupled with quadrupole time-of-flight (QTOF) mass spectrometry (MS) for screening and quantification purposes in pesticide residue analysis. A screening method developed in our laboratory for around 130 pesticides has been applied to fruit and vegetable samples, including strawberries, oranges, apples, carrots, lettuces, courgettes, red peppers, and tomatoes. Samples were analyzed together with quality control samples (at 0.05 mg/kg) for each matrix and for matrix-matched calibration standards. The screening strategy consisted in first rapid searching and detection, and then a refined identification step using the QTOF capabilities (MS(E) and accurate mass). Identification was based on the presence of one characteristic m/z ion (Q) obtained with the low collision energy function and at least one fragment ion (q) obtained with the high collision energy function, both with mass errors of less than 5 ppm, and an ion intensity ratio (q/Q) within the tolerances permitted. Following this strategy, 15 of 130 pesticides were identified in the samples. Afterwards, the quantitation capabilities were tested by performing a quantitative validation for those pesticides detected in the samples. To this aim, five matrices were selected (orange, apple, tomato, lettuce, and carrot) and spiked at two concentrations (0.01 and 0.1 mg/kg), and quantification was done using matrix-matched calibration standards (relative responses versus triphenyl phosphate used as an internal standard). Acceptable average recoveries and relative standard deviations were obtained for many but not all pesticide-matrix combinations. These figures allowed us to perform a retrospective quantification of positives found in the screening without the need for additional analysis. Taking advantage of the accurate-mass full-spectrum data provided by QTOF MS, we searched for a higher number of compounds (up to 416 pesticides) in a second stage by performing extra data processing without any new sample injection. Several more pesticides were detected, confirmed, and/or tentatively identified when the reference standard was unavailable, illustrating in this way the potential of gas chromatography-QTOF MS to detect pesticides in addition to the ones targeted in quantitative analysis of pesticides in food matrices.
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Affiliation(s)
- M I Cervera
- Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, 12071, Castellón, Spain
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112
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Ramasubramanian T, Paramasivam M, Jayanthi R, Chandrasekaran S. A simple and sensitive single-step method for gas chromatography–mass spectrometric determination of fipronil and its metabolites in sugarcane juice, jaggery and sugar. Food Chem 2014; 150:408-13. [DOI: 10.1016/j.foodchem.2013.11.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 09/11/2013] [Accepted: 11/01/2013] [Indexed: 10/26/2022]
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113
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Lan M, Li S, Xu Z, Tian C, Yang M, Gui W, Zhu G. Simultaneous determination of saflufenacil and its two metabolites in soil samples by ultra-performance liquid chromatography with tandem mass spectrometry. J Sep Sci 2014; 37:658-64. [DOI: 10.1002/jssc.201301121] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Revised: 12/08/2013] [Accepted: 12/18/2013] [Indexed: 11/05/2022]
Affiliation(s)
- Meijing Lan
- Institute of Pesticide and Environmental Toxicology; Zhejiang University; Hangzhou P.R. China
| | - Shuying Li
- Institute of Pesticide and Environmental Toxicology; Zhejiang University; Hangzhou P.R. China
| | - Zhenzhen Xu
- Institute of Pesticide and Environmental Toxicology; Zhejiang University; Hangzhou P.R. China
| | - Chunxia Tian
- Institute of Pesticide and Environmental Toxicology; Zhejiang University; Hangzhou P.R. China
| | - Mei Yang
- Institute of Pesticide and Environmental Toxicology; Zhejiang University; Hangzhou P.R. China
| | - Wenjun Gui
- Institute of Pesticide and Environmental Toxicology; Zhejiang University; Hangzhou P.R. China
| | - Guonian Zhu
- Institute of Pesticide and Environmental Toxicology; Zhejiang University; Hangzhou P.R. China
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114
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dell'Oro D, Casamassima F, Gesualdo G, Iammarino M, Mambelli P, Nardelli V. Determination of pyrethroids in chicken egg samples: development and validation of a confirmatory analytical method by gas chromatography/mass spectrometry. Int J Food Sci Technol 2013. [DOI: 10.1111/ijfs.12441] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Daniela dell'Oro
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata; Via Manfredonia 20 Foggia 71121 Italy
| | - Francesco Casamassima
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata; Via Manfredonia 20 Foggia 71121 Italy
| | - Giuseppe Gesualdo
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata; Via Manfredonia 20 Foggia 71121 Italy
| | - Marco Iammarino
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata; Via Manfredonia 20 Foggia 71121 Italy
| | - Paolo Mambelli
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata; Via Manfredonia 20 Foggia 71121 Italy
| | - Valeria Nardelli
- Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata; Via Manfredonia 20 Foggia 71121 Italy
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115
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Detection of the residues of nineteen pesticides in fresh vegetable samples using gas chromatography–mass spectrometry. Food Control 2013. [DOI: 10.1016/j.foodcont.2013.05.006] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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116
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Chai LK, Elie F. A rapid multi-residue method for pesticide residues determination in white and black pepper (Piper nigrum L.). Food Control 2013. [DOI: 10.1016/j.foodcont.2012.12.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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117
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Pesticide residues in fresh-cut vegetables from integrated pest management by ultra performance liquid chromatography coupled to tandem mass spectrometry. Food Control 2013. [DOI: 10.1016/j.foodcont.2012.09.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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118
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Hua J, Cothran R, Stoler A, Relyea R. Cross-tolerance in amphibians: wood frog mortality when exposed to three insecticides with a common mode of action. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2013; 32:932-936. [PMID: 23322537 DOI: 10.1002/etc.2121] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 09/12/2012] [Accepted: 11/19/2012] [Indexed: 06/01/2023]
Abstract
Insecticide tolerance and cross-tolerance in nontarget organisms is often overlooked despite its potential to buffer natural systems from anthropogenic influence. We exposed wood frog tadpoles from 15 populations to three acetylcholine esterase-inhibiting insecticides and found widespread variation in insecticide tolerance and evidence for cross-tolerance to these insecticides. Our results demonstrate that amphibian populations with tolerance to one pesticide may be tolerant to many other pesticides.
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Affiliation(s)
- Jessica Hua
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
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119
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Shoeibi S, Amirahmadi M, Rastegar H, Khosrokhavar R, Khaneghah AM. An Applicable Strategy for Improvement Recovery in Simultaneous Analysis of 20 Pesticides Residue in Tea. J Food Sci 2013; 78:T792-6. [DOI: 10.1111/1750-3841.12100] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 02/03/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Shahram Shoeibi
- Authors Shoeibi, Amirahmadi, Rastegar; Khosrokhavar are with Food and Drug Laboratory Research Center and Food and Drug Reference Control Laboratories Center
| | | | | | | | - Amin Mousavi Khaneghah
- Author Khaneghah is with Dept. of Food Science and Technology; Islamic Azad Univ.; Science and Research Branch; Tehran; Iran
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120
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Freitas SKB, Paim APS, de Souza e Silva PT. Development of a LC-IT-TOF MS Procedure to Quantify Veterinary Drug Residues in Milk Employing a QuEChERS Approach. FOOD ANAL METHOD 2013. [DOI: 10.1007/s12161-013-9595-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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121
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Rajski Ł, Lozano A, Belmonte-Valles N, Uclés A, Uclés S, Mezcua M, Fernandez-Alba AR. Comparison of three multiresidue methods to analyse pesticides in green tea with liquid and gas chromatography/tandem mass spectrometry. Analyst 2013; 138:921-31. [DOI: 10.1039/c2an35995b] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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122
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Evaluation of a new column backflushing set-up in the gas chromatographic–tandem mass spectrometric analysis of pesticide residues in dietary supplements. J Chromatogr A 2012; 1265:155-64. [DOI: 10.1016/j.chroma.2012.09.094] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 09/26/2012] [Accepted: 09/27/2012] [Indexed: 11/22/2022]
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123
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Lao W, Maruya KA, Tsukada D. A Two-Component Mass Balance Model for Calibration of Solid-Phase Microextraction Fibers for Pyrethroids in Seawater. Anal Chem 2012; 84:9362-9. [DOI: 10.1021/ac302120m] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Wenjian Lao
- Southern California Coast Water Research Project, Costa Mesa, California 92626, United States
| | - Keith A. Maruya
- Southern California Coast Water Research Project, Costa Mesa, California 92626, United States
| | - David Tsukada
- Southern California Coast Water Research Project, Costa Mesa, California 92626, United States
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124
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Li L, Sun Z, Li H, Keener TC. Effects of activated carbon surface properties on the adsorption of volatile organic compounds. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2012; 62:1196-1202. [PMID: 23155865 DOI: 10.1080/10962247.2012.700633] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
UNLABELLED Physical and chemical properties of activated carbon (AC) were analyzed to investigate the effects of adsorbate properties on AC adsorption performance. Fixed-bed adsorption experiments were conducted with toluene, acetone, and xylene as adsorbates. From the results, the adsorption capacities of the three adsorbates had the following order: xylene > toluene > acetone. The correlation between experimental data and adsorbate properties was also analyzed. The results showed that different functional groups corresponding to the properties of adsorbates influenced the adsorptive properties of AC differently. The adsorption capacity of AC increased linearly as the molecular weight, dynamic diameter, boiling point, and density of the adsorbate increased. However, adsorption capacity decreased as the polarity index and vapor pressure of the adsorbate increased. For adsorption onto three types of AC, the adsorption energies of the three adsorbates had the following order: xylene > toluene > acetone. IMPLICATIONS This paper focused on the research on adsorption behavior of activated carbon based on adsorbate properties. Adsorption experiments were conducted under the same condition while the adsorbates were toluene, acetone, and xylene, respectively. Correlation analysis between experimental data and adsorbate properties was conducted. The different groups have different influence on the adsorptive properties of ACs. The adsorption capacity of activated carbon increases with the increase of adsorbate molecular weight, dynamic diameter, boiling point, and density, and that this relationship is linear. The relationship between adsorption capacity and the polarity index and vapor pressure of adsorbate shows an opposite trend, and the adsorption capacities and adsorption energies of three kinds of activated carbon for these three adsorbates had the following order: xylene > toluene > acetone.
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Affiliation(s)
- Liqing Li
- School of Energy Science and Engineering, Central South University, Changsha 410083, Hunan Province, PR China.
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125
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Sang ZY, Wang YT, Tsoi YK, Leung KSY. CODEX-compliant eleven organophosphorus pesticides screening in multiple commodities using headspace-solid phase microextraction-gas chromatography-mass spectrometry. Food Chem 2012; 136:710-7. [PMID: 23122118 DOI: 10.1016/j.foodchem.2012.08.060] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 08/09/2012] [Accepted: 08/27/2012] [Indexed: 10/27/2022]
Abstract
A headspace-solid phase microextraction-gas chromatography-mass spectrometric (HS-SPME-GC-MS, hereafter abbreviated as "SPME") method was developed for dedicated organophosphorus (OP) pesticides assessment in multiple vegetable and fruit commodities. Specific extraction variables were optimised to achieve harmonised extraction performance of eleven OPs in a great span of seven characteristic commodities cataloged in Codex Alimentarius Commission. Comprehensive validation study confirmed analytical robustness of the SPME treatment in turnip, green cabbage, French beans, eggplant, apple, nectarine and grapes. Based on range-specific evaluation, extraction of individual OPs was characterised by sub-ppb level sensitivity and a wide 0.01-2.5 mg L(-1) dynamic range. Effective sample clean-up afforded precise quantification (0.5-10.9% R.S.D.) within a 70-120% recovery range at the MRL levels specified for individual commodities. Compared to conventional methods currently used, the SPME treatment developed here is quick, accurate, and relatively environmental friendly; it represents an attractive, practical way to deliver international standards in OP screening routines.
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Affiliation(s)
- Zi-Ye Sang
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region, PR China
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126
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Rapid Determination of Organonitrogen, Organophosphorus and Carbamate Pesticides in Tea by Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry (UPLC-MS/MS). FOOD ANAL METHOD 2012. [DOI: 10.1007/s12161-012-9465-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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127
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Hu Y, Wan L, Zhang J, Yang F, Cao J. Rapid determination of pesticide residues in Chinese materia medica using QuEChERS sample preparation followed by gas chromatography–mass spectrometry. Acta Pharm Sin B 2012. [DOI: 10.1016/j.apsb.2012.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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128
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Application of gas chromatography time-of-flight mass spectrometry for target and non-target analysis of pesticide residues in fruits and vegetables. J Chromatogr A 2012; 1244:168-77. [DOI: 10.1016/j.chroma.2012.04.063] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 04/25/2012] [Accepted: 04/26/2012] [Indexed: 11/22/2022]
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129
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Analytical procedures for the determination of emerging organic contaminants in plant material: A review. Anal Chim Acta 2012; 722:8-20. [DOI: 10.1016/j.aca.2012.02.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 02/01/2012] [Accepted: 02/02/2012] [Indexed: 11/19/2022]
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130
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Chai LK, Zaidel ND, Hansen HCB. A rapid multi-residue method for the determination of pesticide residues in choi sum, yardlong beans and aubergines. Food Chem 2012. [DOI: 10.1016/j.foodchem.2011.09.037] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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131
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Walorczyk S. Gas chromatographic–tandem mass spectrometric analysis of pesticides residues in produce using concurrent solvent recondensation-large volume injection. J Chromatogr A 2012; 1222:98-108. [DOI: 10.1016/j.chroma.2011.12.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2011] [Revised: 11/30/2011] [Accepted: 12/01/2011] [Indexed: 10/14/2022]
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132
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Albaseer SS, Mukkanti K, Rao RN, Swamy Y. Analytical artifacts, sample handling and preservation methods of environmental samples of synthetic pyrethroids. Trends Analyt Chem 2011. [DOI: 10.1016/j.trac.2011.05.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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133
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Planar solid phase extraction—A new clean-up concept in multi-residue analysis of pesticides by liquid chromatography–mass spectrometry. J Chromatogr A 2011; 1218:6540-7. [DOI: 10.1016/j.chroma.2011.06.108] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 06/28/2011] [Accepted: 06/30/2011] [Indexed: 11/19/2022]
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134
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Koesukwiwat U, Lehotay SJ, Leepipatpiboon N. Fast, low-pressure gas chromatography triple quadrupole tandem mass spectrometry for analysis of 150 pesticide residues in fruits and vegetables. J Chromatogr A 2011; 1218:7039-50. [PMID: 21871625 DOI: 10.1016/j.chroma.2011.07.094] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Revised: 07/28/2011] [Accepted: 07/29/2011] [Indexed: 11/25/2022]
Abstract
We developed and evaluated a new method of low-pressure gas chromatography-tandem mass spectrometry (LP-GC/MS-MS) using a triple quadrupole instrument for fast analysis of 150 relevant pesticides in four representative fruits and vegetables. This LP-GC (vacuum outlet) approach entails coupling a 10 m, 0.53 mm i.d., 1 μm film analytical column between the MS transfer line and a 3 m, 0.15 mm i.d. capillary at the inlet. The MS creates a vacuum in the 10 m analytical column, which reduces the viscosity of the He carrier gas and thereby shifts the optimal flow rate to greater velocity. By taking advantage of the H(2)-like properties of He under vacuum, the short analytical column, a rapid oven temperature ramp rate, and the high selectivity and sensitivity of MS/MS, 150 pesticides were separated in <6.5 min. The 2.5 ms dwell time and 1 ms interscan delay of the MS/MS instrument were critical for achieving >8 data points across the 2-3 s wide peaks. To keep dwell and cycle times constant across all peaks, each segment consisted of 30 analytes (60 transitions). For assessment, we injected extracts of spiked broccoli, cantaloupe, lemon, and sweet potato from the updated QuEChERS sample preparation method. Average recoveries (n=72) were 70-120% for 144 of the pesticides, and reproducibilities were <20% RSD for all but 4 analytes. Also, detection limits were <5 ng/g for all but a few pesticides, depending on the matrix. In addition to high quality performance, the method gave excellent reliability and high sample throughput, including easy peak integration to obtain rapid results.
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Affiliation(s)
- Urairat Koesukwiwat
- US Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, PA 19038, USA
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135
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Lehotay SJ, Koesukwiwat U, van der Kamp H, Mol HGJ, Leepipatpiboon N. Qualitative aspects in the analysis of pesticide residues in fruits and vegetables using fast, low-pressure gas chromatography-time-of-flight mass spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:7544-7556. [PMID: 21452898 DOI: 10.1021/jf104606j] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Quantitative method validation is a well-established process to demonstrate trueness and precision of the results with a given method. However, an assessment of qualitative results is also an important need to estimate selectivity and devise criteria for chemical identification when using the method, particularly for mass spectrometric analysis. For multianalyte analysis, automatic instrument software is commonly used to make initial qualitative identifications of the target analytes by comparison of their mass spectra against a database library. Especially at low residue levels in complex matrices, manual checking of results is typically needed to correct the peak assignments and integration errors, which is very time-consuming. Low-pressure gas chromatography-mass spectrometry (LP-GC-MS) has been demonstrated to increase the speed of analysis for GC-amenable residues in various foods and provide more advantages over the traditional GC-MS approach. LP-GC-MS on a time-of-flight (ToF) instrument was used, which provided high sample throughput with <10 min analysis time. The method had already been validated to be acceptable quantitatively for nearly 150 pesticides, and in this study of qualitative performance, 90 samples in total of strawberry, tomato, potato, orange, and lettuce extracts from the QuEChERS sample preparation approach were analyzed. The extracts were randomly spiked with different pesticides at different levels, both unknown to the analyst, in the different matrices. Automated software evaluation was compared with human assessments in terms of false-positive and -negative results. Among the 13590 possible permutations with 696 blind additions made, the automated software approach yielded 1.2% false presumptive positives with 23% false negatives, whereas the analyst achieved 0.8% false presumptive positives and 17% false negatives for the same analytical data files. False negatives frequently occurred due to challenges at the lowest concentrations, but 70% of them involved certain pesticides that degraded (e.g., captafol, folpet) or otherwise could not be detected. The false-negative rate was reduced to 5-10% if the problematic analytes were excluded. Despite its somewhat better performance in this study, the analyst approach was extremely time-consuming and would not be practical in high sample throughput applications for so many analytes in complicated matrices.
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136
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Lee SW, Choi JH, Cho SK, Yu HA, Abd El-Aty A, Shim JH. Development of a new QuEChERS method based on dry ice for the determination of 168 pesticides in paprika using tandem mass spectrometry. J Chromatogr A 2011; 1218:4366-77. [DOI: 10.1016/j.chroma.2011.05.021] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 05/05/2011] [Accepted: 05/08/2011] [Indexed: 11/17/2022]
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137
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Analysis of pesticide residues in sugarcane juice using QuEChERS sample preparation and gas chromatography with electron capture detection. Food Chem 2011. [DOI: 10.1016/j.foodchem.2010.11.074] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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138
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139
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Kolberg DI, Prestes OD, Adaime MB, Zanella R. Development of a fast multiresidue method for the determination of pesticides in dry samples (wheat grains, flour and bran) using QuEChERS based method and GC–MS. Food Chem 2011. [DOI: 10.1016/j.foodchem.2010.10.041] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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140
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Han Y, Jia X, Liu X, Duan T, Chen H. Dispersive solid-phase extraction combined with dispersive liquid-liquid microextraction for the determination of polybrominated diphenyl ethers in plastic bottled beverage by GC-MS. J Sep Sci 2011; 34:1047-54. [DOI: 10.1002/jssc.201000631] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Revised: 12/21/2010] [Accepted: 02/04/2011] [Indexed: 11/11/2022]
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141
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Choi JH, Yoon HJ, Do JA, Park YC, Kim JH, Choi D. An analytical method for prohexadione in Chinese cabbage and apple. Biomed Chromatogr 2011; 25:493-7. [DOI: 10.1002/bmc.1472] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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142
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Lehotay SJ. QuEChERS sample preparation approach for mass spectrometric analysis of pesticide residues in foods. Methods Mol Biol 2011; 747:65-91. [PMID: 21643905 DOI: 10.1007/978-1-61779-136-9_4] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This chapter describes an easy, rapid, and low-cost sample preparation approach for the determination of pesticide residues in foods using gas and/or liquid chromatographic (GC and/or LC) analytical separation and mass spectrometric (MS) detection. The approach is known as QuEChERS, which stands for "quick, easy, cheap, effective, rugged, and safe." Originally, QuEChERS was a particular "method" for pesticide residue analysis, but it is very flexible and has evolved into an "approach," which has been used in many methods, and not just for pesticide residues. Two of the QuEChERS versions using buffering have been validated in interlaboratory trials for dozens of pesticides in several food matrices, and both have successfully met performance criteria to achieve "official" status from international standard organizations (AOAC Official Method 2007.01 and CEN Standard Method EN 15662). The main aspects of the QuEChERS approach consists of extraction of a well-homogenized sample by shaking with solvent (typically acetonitrile) in a centrifuge tube, salt-out partitioning of water with salts including magnesium sulfate (MgSO(4)), and cleanup using "dispersive solid-phase extraction" (dSPE), in which common matrix components are retained by sorbent(s) and the analytes remain in the extract. For widest analytical scope, concurrent analysis is done for hundreds of pesticides using GC-MS(/MS) and LC-MS/MS. The aim of this chapter is to review the QuEChERS sample preparation methodology and provide a summary of up-to-date information with modification options depending on the application needs.
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Affiliation(s)
- Steven J Lehotay
- United States Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, PA, USA.
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143
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de Pinho GP, Neves AA, de Queiroz MELR, Silvério FO. Optimization of the liquid–liquid extraction method and low temperature purification (LLE–LTP) for pesticide residue analysis in honey samples by gas chromatography. Food Control 2010. [DOI: 10.1016/j.foodcont.2010.03.006] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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144
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Rapid determination of organophosphorous pesticides in leeks by gas chromatography–triple quadrupole mass spectrometry. Food Chem 2010. [DOI: 10.1016/j.foodchem.2010.02.038] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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145
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Determination of 215 pesticide residues in ginger using liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Se Pu 2010; 28:579-89. [DOI: 10.3724/sp.j.1123.2010.00579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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146
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Pesticide determination in tomatoes by solid–liquid extraction with purification at low temperature and gas chromatography. Food Chem 2010. [DOI: 10.1016/j.foodchem.2009.11.080] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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147
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An overview of sample preparation and extraction of synthetic pyrethroids from water, sediment and soil. J Chromatogr A 2010; 1217:5537-54. [PMID: 20650460 DOI: 10.1016/j.chroma.2010.06.058] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2009] [Revised: 05/29/2010] [Accepted: 06/23/2010] [Indexed: 11/22/2022]
Abstract
The latest developments in sample preparation and extraction of synthetic pyrethroids from environmental matrices viz., water, sediment and soil were reviewed. Though the synthetic pyrethroids were launched in 1970s, to the best of authors' knowledge there was no review on this subject until date. The present status and recent advances made during the last 10 years in sample preparation including conservation and extraction techniques used in determination of synthetic pyrethroids in water, sediment and soil were discussed. Pre- and post-extraction treatments, sample stability during extraction and its influence upon the whole process of analytical determination were covered. Relative merits and demerits including the green aspects of extraction were evaluated. The current trends and future prospects were also addressed.
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148
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Guo B, Huang Z, Wang M, Wang X, Zhang Y, Chen B, Li Y, Yan H, Yao S. Simultaneous direct analysis of benzimidazole fungicides and relevant metabolites in agricultural products based on multifunction dispersive solid-phase extraction and liquid chromatography–mass spectrometry. J Chromatogr A 2010; 1217:4796-807. [DOI: 10.1016/j.chroma.2010.05.025] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2010] [Revised: 05/03/2010] [Accepted: 05/17/2010] [Indexed: 11/26/2022]
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149
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Chamberlain EF, Wang C, Shi H, Adams CD, Ma Y. Oxidative removal and kinetics of fipronil in various oxidation systems for drinking water treatment. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:6895-6899. [PMID: 20455564 DOI: 10.1021/jf100872f] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Fipronil, a pesticide gaining wide usage, was oxidized with common drinking water treatment disinfectants and oxidants; with a degradate identified using liquid chromatography-mass spectrometry. Oxidants investigated were free chlorine (HOCl/OCl(-)), monochloramine (ClNH(2)), chlorine dioxide (ClO(2)), and permanganate (MnO(4)(-)) at pH 6.6 and 8.6. Free chlorine, chlorine dioxide, and permanganate were reactive with fipronil to various degrees, whereas monochloramine was only marginally reactive. No oxidation products were observed for free chlorine, monochloramine, or chlorine dioxide. Oxidation by permanganate produced an identifiable degradate, fipronil sulfone, which was recalcitrant to further oxidation by permanganate. Fipronil sulfone could, however, be further degraded by free chlorine. Under typical conditions of water treatment, free chlorine was an effective oxidant for fipronil and fipronil sulfone, achieving partial removal at typical conditions. pH effects were observed for free chlorine, chlorine dioxide, and permanganate with more rapid oxidation occurring at pH 8.6 than at pH 6.6.
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Affiliation(s)
- Evelyn F Chamberlain
- Department of Civil, Architectural and Environmental Engineering and Environmental Research Center, Missouri University of Science and Technology, Rolla, Missouri 65409, USA
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150
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Koesukwiwat U, Lehotay SJ, Miao S, Leepipatpiboon N. High throughput analysis of 150 pesticides in fruits and vegetables using QuEChERS and low-pressure gas chromatography-time-of-flight mass spectrometry. J Chromatogr A 2010; 1217:6692-703. [PMID: 20627307 DOI: 10.1016/j.chroma.2010.05.012] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 04/30/2010] [Accepted: 05/04/2010] [Indexed: 11/17/2022]
Abstract
A higher monitoring rate is highly desirable in the labs, but this goal is typically limited by sample throughput. In this study, we sought to assess the real-world applicability of fast, low-pressure GC-time-of-flight MS (LP-GC/TOFMS) for the identification and quantification of 150 pesticides in tomato, strawberry, potato, orange, and lettuce samples. Buffered and unbuffered versions of QuEChERS (which stands for "quick, easy, cheap, effective, rugged, and safe") using dispersive solid-phase extraction (d-SPE) and disposable pipette extraction (DPX) for clean-up were compared for sample preparation. For clean-up of all sample types, a combination of 150 mg MgSO₄, 50mg primary secondary amine (PSA), 50 mg C₁₈, and 7.5 mg graphitized carbon black (GCB) per mL extract was used. No significant differences were observed in the results between the different sample preparation versions. QuEChERS took < 10 min per individual sample, or < 1 h for two chemists to prepare 32 pre-homogenized samples, and using LP-GC/TOFMS, < 10 min run time and < 15 min cycle time allowed > 32 injections in 8 h. Overall, > 126 analytes gave recoveries (3 spiking levels) in the range of 70-120% with < 20% RSD. The results indicate that LP-GC/TOFMS for GC-amenable analytes matches UHPLC-MS/MS in terms of sample throughput and turnaround time for their routine, concurrent use in the analysis of a wide range of analytes in QuEChERS extracts to achieve reliable quantification and identification of pesticide residues in foods.
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Affiliation(s)
- Urairat Koesukwiwat
- US Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, PA 19038, USA
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