1
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Perraud V, Li X, Smith JN, Finlayson-Pitts BJ. Novel ionization reagent for the measurement of gas-phase ammonia and amines using a stand-alone atmospheric pressure gas chromatography (APGC) source. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34:e8561. [PMID: 31429122 DOI: 10.1002/rcm.8561] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 08/14/2019] [Accepted: 08/14/2019] [Indexed: 06/10/2023]
Abstract
RATIONALE Contaminants present in ambient air or in sampling lines can interfere with the target analysis through overlapping peaks or causing a high background. This study presents a positive outcome from the unexpected presence of N-methyl-2-pyrrolidone, released from a PALL HEPA filter, in the analysis of atmospherically relevant gas-phase amines using chemical ionization mass spectrometry. METHODS Gas-phase measurements were performed using a triple quadrupole mass spectrometer equipped with a modified atmospheric pressure gas chromatography (APGC) source which allows sampling of the headspace above pure amine standards. Gas-phase N-methyl-2-pyrrolidone (NMP) emitted from a PALL HEPA filter located in the inlet stream served as the ionizing agent. RESULTS This study demonstrates that some alkylamines efficiently form a [NMP + amine+H]+ cluster with NMP upon chemical ionization at atmospheric pressure. The extent of cluster formation depends largely on the proton affinity of the amine compared with that of NMP. Aromatic amines (aniline, pyridine) and diamines (putrescine) were shown not to form cluster ions with NMP. CONCLUSIONS The use of NMP as an ionizing agent with stand-alone APGC provided high sensitivity for ammonia and the smaller amines. The main advantages, in addition to sensitivity, are direct sampling into the APGC source and avoiding uptake on sampling lines which can be a significant problem with ammonia and amines.
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Affiliation(s)
- Véronique Perraud
- Department of Chemistry, University of California, Irvine, CA, 92697, USA
| | - Xiaoxiao Li
- Department of Chemistry, University of California, Irvine, CA, 92697, USA
| | - James N Smith
- Department of Chemistry, University of California, Irvine, CA, 92697, USA
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2
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Hennig K, Antignac JP, Bichon E, Morvan ML, Miran I, Delaloge S, Feunteun J, Le Bizec B. Steroid hormone profiling in human breast adipose tissue using semi-automated purification and highly sensitive determination of estrogens by GC-APCI-MS/MS. Anal Bioanal Chem 2017; 410:259-275. [PMID: 29147745 DOI: 10.1007/s00216-017-0717-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 09/22/2017] [Accepted: 10/18/2017] [Indexed: 01/08/2023]
Abstract
Body mass index is a known breast cancer risk factor due to, among other mechanisms, adipose-derived hormones. We developed a method for steroid hormone profiling in adipose tissue to evaluate healthy tissue around the tumor and define new biomarkers for cancer development. A semi-automated sample preparation method based on gel permeation chromatography and subsequent derivatization with trimethylsilyl (TMS) is presented. Progestagens and androgens were determined by GC-EI-MS/MS (LOQ 0.5 to 10 ng/g lipids). For estrogen measurement, a highly sensitive GC-APCI-MS/MS method was developed to reach the required lower limits of detection (0.05 to 0.1 ng/g lipids in matrix, 100-200 fg on column for pure standards). The combination of the two methods allows the screening of 27 androgens and progestagens and 4 estrogens from a single sample. Good accuracies and repeatabilities were achieved for each compound class at their respective limit of detection. The method was applied to determine steroid hormone profiles in adipose tissue of 51 patients, collected both at proximity and distant to the tumor. Out of the 31 tested steroid hormones, 14 compounds were detected in human samples. Pregnenolone, 17-hydroxypregnenolone, dehydroepiandrosterone (DHEA), and androstendione accounted together for 80% of the observed steroid hormone profiles, whereas the estrogens accounted for only 1%. These profiles did not differ based on sampling location, except for ß-estradiol; steroid hormone conversions from androgens to estrogens that potentially take place in adipose or tumoral tissue might not be detectable due a factor 100 difference in concentration of for example DHEA and ß-estradiol. Graphical Abstract Schematic overview of the determination of steroid hormones and metabolites in adipose tissue in proximity and distal to the tumor.
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Affiliation(s)
- Kristin Hennig
- Laboratoire d'Etude des Résidus et Contaminants dans les Aliments (LABERCA), ONIRIS, LUNAM Université, 44307, Nantes, France
| | - Jean Philippe Antignac
- Laboratoire d'Etude des Résidus et Contaminants dans les Aliments (LABERCA), ONIRIS, LUNAM Université, 44307, Nantes, France.
| | - Emmanuelle Bichon
- Laboratoire d'Etude des Résidus et Contaminants dans les Aliments (LABERCA), ONIRIS, LUNAM Université, 44307, Nantes, France
| | - Marie-Line Morvan
- Laboratoire d'Etude des Résidus et Contaminants dans les Aliments (LABERCA), ONIRIS, LUNAM Université, 44307, Nantes, France
| | - Isabelle Miran
- UMR981 INSERM, Gustave Roussy, Paris-Saclay University, 94805, Villejuif, France
| | - Suzette Delaloge
- Breast Cancer Group, Gustave Roussy Cancer Campus, 94805, Villejuif, France
| | - Jean Feunteun
- UMR8200 CNRS, Gustave Roussy, Paris-Saclay University, 94805, Villejuif, France
| | - Bruno Le Bizec
- Laboratoire d'Etude des Résidus et Contaminants dans les Aliments (LABERCA), ONIRIS, LUNAM Université, 44307, Nantes, France
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3
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Zheng X, Zhang P, Liao B, Li J, Liu X, Shi Y, Cheng J, Lai Z, Xu J, Chen S. A Comprehensive Quality Evaluation System for Complex Herbal Medicine Using PacBio Sequencing, PCR-Denaturing Gradient Gel Electrophoresis, and Several Chemical Approaches. FRONTIERS IN PLANT SCIENCE 2017; 8:1578. [PMID: 28955365 PMCID: PMC5601397 DOI: 10.3389/fpls.2017.01578] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/29/2017] [Indexed: 06/01/2023]
Abstract
Herbal medicine is a major component of complementary and alternative medicine, contributing significantly to the health of many people and communities. Quality control of herbal medicine is crucial to ensure that it is safe and sound for use. Here, we investigated a comprehensive quality evaluation system for a classic herbal medicine, Danggui Buxue Formula, by applying genetic-based and analytical chemistry approaches to authenticate and evaluate the quality of its samples. For authenticity, we successfully applied two novel technologies, third-generation sequencing and PCR-DGGE (denaturing gradient gel electrophoresis), to analyze the ingredient composition of the tested samples. For quality evaluation, we used high performance liquid chromatography assays to determine the content of chemical markers to help estimate the dosage relationship between its two raw materials, plant roots of Huangqi and Danggui. A series of surveys were then conducted against several exogenous contaminations, aiming to further access the efficacy and safety of the samples. In conclusion, the quality evaluation system demonstrated here can potentially address the authenticity, quality, and safety of herbal medicines, thus providing novel insight for enhancing their overall quality control. Highlight: We established a comprehensive quality evaluation system for herbal medicine, by combining two genetic-based approaches third-generation sequencing and DGGE (denaturing gradient gel electrophoresis) with analytical chemistry approaches to achieve the authentication and quality connotation of the samples.
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Affiliation(s)
- Xiasheng Zheng
- Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine, Institute of Chinese Materia Medica, China Academy of Chinese Medical SciencesBeijing, China
- Key Laboratory of Technologies and Applications of Ultrafine Granular Powder of Herbal Medicine, State Administration of Traditional Chinese Medicine, Zhongshan Zhongzhi Pharmaceutical Group LimitedZhongshan, China
- Guangdong Provincial Key Laboratory of New Drug Development and Research of Chinese Medicine, Guangzhou University of Chinese MedicineGuangzhou, China
| | - Peng Zhang
- Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine, Institute of Chinese Materia Medica, China Academy of Chinese Medical SciencesBeijing, China
- School of Chinese Materia Medica, Beijing University of Chinese MedicineBeijing, China
| | - Baosheng Liao
- Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine, Institute of Chinese Materia Medica, China Academy of Chinese Medical SciencesBeijing, China
| | - Jing Li
- Traditional Chinese Medicine Gynecology Laboratory in Lingnan Medical Research Center, Guangzhou University of Chinese MedicineGuangzhou, China
| | - Xingyun Liu
- Key Laboratory of Technologies and Applications of Ultrafine Granular Powder of Herbal Medicine, State Administration of Traditional Chinese Medicine, Zhongshan Zhongzhi Pharmaceutical Group LimitedZhongshan, China
| | - Yuhua Shi
- Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine, Institute of Chinese Materia Medica, China Academy of Chinese Medical SciencesBeijing, China
| | - Jinle Cheng
- Key Laboratory of Technologies and Applications of Ultrafine Granular Powder of Herbal Medicine, State Administration of Traditional Chinese Medicine, Zhongshan Zhongzhi Pharmaceutical Group LimitedZhongshan, China
| | - Zhitian Lai
- Key Laboratory of Technologies and Applications of Ultrafine Granular Powder of Herbal Medicine, State Administration of Traditional Chinese Medicine, Zhongshan Zhongzhi Pharmaceutical Group LimitedZhongshan, China
| | - Jiang Xu
- Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine, Institute of Chinese Materia Medica, China Academy of Chinese Medical SciencesBeijing, China
| | - Shilin Chen
- Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine, Institute of Chinese Materia Medica, China Academy of Chinese Medical SciencesBeijing, China
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4
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Ten Dam G, Pussente IC, Scholl G, Eppe G, Schaechtele A, van Leeuwen S. The performance of atmospheric pressure gas chromatography-tandem mass spectrometry compared to gas chromatography-high resolution mass spectrometry for the analysis of polychlorinated dioxins and polychlorinated biphenyls in food and feed samples. J Chromatogr A 2016; 1477:76-90. [PMID: 27894695 DOI: 10.1016/j.chroma.2016.11.035] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 11/12/2016] [Accepted: 11/20/2016] [Indexed: 11/17/2022]
Abstract
Recently, gas chromatography tandem mass spectrometry (GC-MS/MS) has been added in European Union (EU) legislation as an alternative to magnetic sector high resolution mass spectrometry (HRMS) for the analysis of dioxins and dioxin like polychlorinated biphenyls (dl-PCB) in food and feed. In this study the performance of APGC-MS/MS compared to GC-HRMS is investigated and compared with EU legislation. The study includes the legislative parameters, relative intermediate precision standard deviation (SRw,rel), trueness, sensitivity, linear range and ion ratio tolerance. In addition, over 200 real samples of large variety and spanning several orders of magnitude in concentration were analyzed by both techniques and the selectivity was evaluated by comparing chromatograms. The SRw,rel and trueness were evaluated using (in-house) reference samples and fulfill to EU legislation, though the SRw,rel was better with GC-HRMS. The sensitivity was considerably better than of GC-HRMS while the linear range was similar. Ion ratios were mostly within the tolerable range of ±15%. A (temporary unresolved) systematic deviation in ion ratio was observed for several congeners, yet this did not lead to exceeding of the maximum ion ratio limits. The APGC-MS/MS results for the non-dioxin-like-PCBs (ndl-PCBs) were negatively biased, particularly for PCB138 and 153 in contaminated samples. The selectivity of APGC-MS/MS was lower for several matrices. Particularly for contaminated samples, interfering peaks were observed in the APGC chromatograms of the native compounds (dioxins) and labeled internal standards (PCBs). These can lead to biased results and ultimately to false positive samples. It was concluded that the determination of dioxins and PCBs using APGC-MS/MS meets the requirements set by the European Commission. However, due to generally better selectivity and SRw,rel, GC-HRMS is the preferred method for monitoring purposes.
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Affiliation(s)
- Guillaume Ten Dam
- RIKILT, Wageningen University and Research, PO Box 230, NL-6700 AE Wageningen, The Netherlands.
| | | | - Georges Scholl
- Center for Analytical Research and Technology (CART), University of Liège, 11 Allée du six AoÛt, Quartier Agora, Belgium
| | - Gauthier Eppe
- Center for Analytical Research and Technology (CART), University of Liège, 11 Allée du six AoÛt, Quartier Agora, Belgium
| | - Alexander Schaechtele
- EU Reference Laboratory (EU-RL) for Dioxins and PCBs in Feed and Food, State Institute for Chemical and Veterinary Analysis of Food, Bissierstrasse 5, 79114 Freiburg, Germany
| | - Stefan van Leeuwen
- RIKILT, Wageningen University and Research, PO Box 230, NL-6700 AE Wageningen, The Netherlands
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5
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van Bavel B, Geng D, Cherta L, Nácher-Mestre J, Portolés T, Ábalos M, Sauló J, Abad E, Dunstan J, Jones R, Kotz A, Winterhalter H, Malisch R, Traag W, Hagberg J, Ericson Jogsten I, Beltran J, Hernández F. Atmospheric-Pressure Chemical Ionization Tandem Mass Spectrometry (APGC/MS/MS) an Alternative to High-Resolution Mass Spectrometry (HRGC/HRMS) for the Determination of Dioxins. Anal Chem 2015; 87:9047-53. [DOI: 10.1021/acs.analchem.5b02264] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bert van Bavel
- MTM
Research Centre, School of Science and Technology, Örebro University, 701 82 Örebro, Sweden
| | - Dawei Geng
- MTM
Research Centre, School of Science and Technology, Örebro University, 701 82 Örebro, Sweden
| | - Laura Cherta
- Research
Institute for Pesticides and Water (IUPA), Avda. Sos Baynat s/n, University Jaume I, 12071 Castellón, Spain
| | - Jaime Nácher-Mestre
- Research
Institute for Pesticides and Water (IUPA), Avda. Sos Baynat s/n, University Jaume I, 12071 Castellón, Spain
| | - Tania Portolés
- Research
Institute for Pesticides and Water (IUPA), Avda. Sos Baynat s/n, University Jaume I, 12071 Castellón, Spain
| | - Manuela Ábalos
- MTM
Research Centre, School of Science and Technology, Örebro University, 701 82 Örebro, Sweden
- Laboratory
of Dioxins, Mass Spectrometry Laboratory, Department of Environmental
Chemistry, IDAEA-CSIC, Jordi Girona 18, 08034 Barcelona, Spain
| | - Jordi Sauló
- Laboratory
of Dioxins, Mass Spectrometry Laboratory, Department of Environmental
Chemistry, IDAEA-CSIC, Jordi Girona 18, 08034 Barcelona, Spain
| | - Esteban Abad
- Laboratory
of Dioxins, Mass Spectrometry Laboratory, Department of Environmental
Chemistry, IDAEA-CSIC, Jordi Girona 18, 08034 Barcelona, Spain
| | | | - Rhys Jones
- Waters Corporation, Manchester, United Kingdom
| | - Alexander Kotz
- EU
Reference Laboratory (EURL) for Dioxins and PCBs in Feed and Food, State Institute for Chemical and Veterinary Analysis of Food, D-79114 Freiburg, Germany
| | - Helmut Winterhalter
- EU
Reference Laboratory (EURL) for Dioxins and PCBs in Feed and Food, State Institute for Chemical and Veterinary Analysis of Food, D-79114 Freiburg, Germany
| | - Rainer Malisch
- EU
Reference Laboratory (EURL) for Dioxins and PCBs in Feed and Food, State Institute for Chemical and Veterinary Analysis of Food, D-79114 Freiburg, Germany
| | - Wim Traag
- RIKILT, Institute of
Food Safety, PO Box 230, NL-6700 AE Wageningen, The Netherlands
| | - Jessika Hagberg
- MTM
Research Centre, School of Science and Technology, Örebro University, 701 82 Örebro, Sweden
| | - Ingrid Ericson Jogsten
- MTM
Research Centre, School of Science and Technology, Örebro University, 701 82 Örebro, Sweden
| | - Joaquim Beltran
- Research
Institute for Pesticides and Water (IUPA), Avda. Sos Baynat s/n, University Jaume I, 12071 Castellón, Spain
| | - Félix Hernández
- Research
Institute for Pesticides and Water (IUPA), Avda. Sos Baynat s/n, University Jaume I, 12071 Castellón, Spain
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6
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Wachsmuth CJ, Dettmer K, Lang SA, Mycielska ME, Oefner PJ. Continuous water infusion enhances atmospheric pressure chemical ionization of methyl chloroformate derivatives in gas chromatography coupled to time-of-flight mass spectrometry-based metabolomics. Anal Chem 2014; 86:9186-95. [PMID: 25152309 DOI: 10.1021/ac502133r] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The effects of continuous water infusion on efficiency and repeatability of atmospheric pressure chemical ionization of both methyl chloroformate (MCF) and methoxime-trimethylsilyl (MO-TMS) derivatives of metabolites were evaluated using gas chromatography-time-of-flight mass spectrometry. Water infusion at a flow-rate of 0.4 mL/h yielded not only an average 16.6-fold increase in intensity of the quasimolecular ion for 20 MCF-derivatized metabolite standards through suppression of in-source fragmentation but also the most repeatable peak area integrals. The impact of water infusion was the greatest for dicarboxylic acids and the least for (hetero-) aromatic compounds. Water infusion also improved the ability to detect reliably fold changes as small as 1.33-fold for the same 20 MCF-derivatized metabolite standards spiked into a human serum extract. On the other hand, MO-TMS derivatives were not significantly affected by water infusion, neither in their fragmentation patterns nor with regard to the detection of differentially regulated compounds. As a proof of principle, we applied MCF derivatization and GC-APCI-TOFMS to the detection of changes in abundance of metabolites in pancreatic cancer cells upon treatment with 17-DMAG. Water infusion increased not only the number of metabolites identified via their quasimolecular ion but also the reproducibility of peak areas, thereby almost doubling the number of significantly regulated metabolites (false discovery rate < 0.05) to a total of 23.
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Affiliation(s)
- Christian J Wachsmuth
- Institute of Functional Genomics, University of Regensburg , Josef-Engert-Strasse 9, 93053 Regensburg, Germany
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7
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Raro M, Portolés T, Sancho JV, Pitarch E, Hernández F, Marcos J, Ventura R, Gómez C, Segura J, Pozo OJ. Mass spectrometric behavior of anabolic androgenic steroids using gas chromatography coupled to atmospheric pressure chemical ionization source. Part I: ionization. JOURNAL OF MASS SPECTROMETRY : JMS 2014; 49:509-521. [PMID: 24913403 DOI: 10.1002/jms.3367] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 03/13/2014] [Accepted: 03/14/2014] [Indexed: 06/03/2023]
Abstract
The detection of anabolic androgenic steroids (AAS) is one of the most important topics in doping control analysis. Gas chromatography coupled to (tandem) mass spectrometry (GC-MS(/MS)) with electron ionization and liquid chromatography coupled to tandem mass spectrometry have been traditionally applied for this purpose. However, both approaches still have important limitations, and, therefore, detection of all AAS is currently afforded by the combination of these strategies. Alternative ionization techniques can minimize these drawbacks and help in the implementation of a single method for the detection of AAS. In the present work, a new atmospheric pressure chemical ionization (APCI) source commercialized for gas chromatography coupled to a quadrupole time-of-flight analyzer has been tested to evaluate the ionization of 60 model AAS. Underivatized and trimethylsylil (TMS)-derivatized compounds have been investigated. The use of GC-APCI-MS allowed for the ionization of all AAS assayed irrespective of their structure. The presence of water in the source as modifier promoted the formation of protonated molecules ([M+H](+)), becoming the base peak of the spectrum for the majority of studied compounds. Under these conditions, [M+H](+), [M+H-H2O](+) and [M+H-2·H2O](+) for underivatized AAS and [M+H](+), [M+H-TMSOH](+) and [M+H-2·TMSOH](+) for TMS-derivatized AAS were observed as main ions in the spectra. The formed ions preserve the intact steroid skeleton, and, therefore, they might be used as specific precursors in MS/MS-based methods. Additionally, a relationship between the relative abundance of these ions and the AAS structure has been established. This relationship might be useful in the structural elucidation of unknown metabolites.
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Affiliation(s)
- M Raro
- Research Institute for Pesticides and Water, University Jaume I, E-12071, Castellón, Spain
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8
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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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9
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Matysik S, Schmitz G, Bauer S, Kiermaier J, Matysik FM. Potential of gas chromatography–atmospheric pressure chemical ionization–time-of-flight mass spectrometry for the determination of sterols in human plasma. Biochem Biophys Res Commun 2014; 446:751-5. [DOI: 10.1016/j.bbrc.2014.01.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Accepted: 01/12/2014] [Indexed: 11/26/2022]
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10
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Ballesteros-Gómez A, de Boer J, Leonards PEG. Novel Analytical Methods for Flame Retardants and Plasticizers Based on Gas Chromatography, Comprehensive Two-Dimensional Gas Chromatography, and Direct Probe Coupled to Atmospheric Pressure Chemical Ionization-High Resolution Time-of-Flight-Mass Spectrometry. Anal Chem 2013; 85:9572-80. [DOI: 10.1021/ac4017314] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ana Ballesteros-Gómez
- Institute for Environmental
Studies, VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Jacob de Boer
- Institute for Environmental
Studies, VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | - Pim E. G. Leonards
- Institute for Environmental
Studies, VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
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11
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Cherta L, Portolés T, Beltran J, Pitarch E, Mol JGJ, Hernández F. Application of gas chromatography-(triple quadrupole) mass spectrometry with atmospheric pressure chemical ionization for the determination of multiclass pesticides in fruits and vegetables. J Chromatogr A 2013; 1314:224-40. [PMID: 24070626 DOI: 10.1016/j.chroma.2013.09.029] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 09/06/2013] [Accepted: 09/08/2013] [Indexed: 10/26/2022]
Abstract
A multi-residue method for the determination of 142 pesticide residues in fruits and vegetables has been developed using a new atmospheric pressure chemical ionization (APCI) source for coupling gas chromatography (GC) to tandem mass spectrometry (MS). Selected reaction monitoring (SRM) mode has been applied, acquiring three transitions for each compound. In contrast to the extensive fragmentation typically obtained in classical electron ionization (EI), the soft APCI ionization allowed the selection of highly abundant protonated molecules ([M+H](+)) as precursor ions for most compounds. This was favorable for both sensitivity and selectivity. Validation of the method was performed in which both quantitative and qualitative parameters were assessed using orange, tomato and carrot samples spiked at two levels, 0.01 and 0.1mg/kg. The QuEChERS method was used for sample preparation, followed by a 10-fold dilution of the final acetonitrile extract with a mixture of hexane and acetone. Recovery and precision were satisfactory in the three matrices, at both concentration levels. Very low limits of detection (down 0.01μg/kg for the most sensitive compounds) were achieved. Ion ratios were consistent and identification according to EU criteria was possible in 80% (0.01mg/kg) to 96% (0.1mg/kg) of the pesticide/matrix combinations. The method was applied to the analysis of various fruits and vegetables from the Mediterranean region of Spain.
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Affiliation(s)
- Laura Cherta
- Research Institute for Pesticides and Water, University Jaume I, 12071 Castellón, Spain
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12
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Portolés T, Mol JGJ, Sancho JV, Hernández F. Advantages of Atmospheric Pressure Chemical Ionization in Gas Chromatography Tandem Mass Spectrometry: Pyrethroid Insecticides as a Case Study. Anal Chem 2012; 84:9802-10. [DOI: 10.1021/ac301699c] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- T. Portolés
- Research Institute for Pesticides
and Water, University Jaume I, 12071 Castellón,
Spain
- RIKILT Institute
of Food Safety, Wageningen University and Research Centre, Akkermaalsbos
2, 6708 WB, Wageningen, The Netherlands
| | - J. G. J. Mol
- RIKILT Institute
of Food Safety, Wageningen University and Research Centre, Akkermaalsbos
2, 6708 WB, Wageningen, The Netherlands
| | - J. V. Sancho
- Research Institute for Pesticides
and Water, University Jaume I, 12071 Castellón,
Spain
| | - F. Hernández
- Research Institute for Pesticides
and Water, University Jaume I, 12071 Castellón,
Spain
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13
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Portolés T, Cherta L, Beltran J, Hernández F. Improved gas chromatography-tandem mass spectrometry determination of pesticide residues making use of atmospheric pressure chemical ionization. J Chromatogr A 2012; 1260:183-92. [PMID: 22959847 DOI: 10.1016/j.chroma.2012.08.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 07/31/2012] [Accepted: 08/02/2012] [Indexed: 02/07/2023]
Abstract
The capabilities of a recently launched atmospheric pressure chemical ionization (APCI) source for mass spectrometry (MS) coupled to gas chromatography (GC) have been tested in order to evaluate its potential in pesticide residue analysis in fruits and vegetables. Twenty-five pesticides were selected due to their high fragmentation under electron ionization (EI), making that the molecular ion (M+) is practically absent in their spectra. The fragmentation of these pesticides under APCI conditions was studied, with the result that M+ was not only present but also highly abundant for most compounds, with noticeable differences in the fragmentation patterns in comparison with EI. Moreover, the addition of water as modifier was tested to promote the formation of protonated molecules ([M+H]+). Under these conditions, [M+H]+ became the base peak of the spectrum for the majority of compounds, thus leading to an increase of sensitivity in the subsequent GC-MS/MS method developed using triple quadrupole analyzer (QqQ). Highly satisfactory sensitivity and precision, in terms of repeatability, were reached and linearity was satisfactory in the range 0.01-100 ng/mL. The developed methodology was applied to apple, orange, tomato and carrot QuEChERS fortified extracts in order to evaluate the matrix effects. In summary, the soft and reproducible ionization in the APCI source has greatly favored the formation of [M+H]+ oppositely to EI where abundant fragmentation occurs and where the molecular ions have low abundance or are even absent in the mass spectrum. In this way, the use of APCI has facilitated the development of tandem MS methods based on the selection of abundant [M+H]+ as precursor ion.
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Affiliation(s)
- Tania Portolés
- Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellón, Spain.
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Wachsmuth CJ, Almstetter MF, Waldhier MC, Gruber MA, Nürnberger N, Oefner PJ, Dettmer K. Performance Evaluation of Gas Chromatography–Atmospheric Pressure Chemical Ionization–Time-of-Flight Mass Spectrometry for Metabolic Fingerprinting and Profiling. Anal Chem 2011; 83:7514-22. [DOI: 10.1021/ac201719d] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christian J. Wachsmuth
- Institute of Functional Genomics, University of Regensburg, Josef-Engert-Straße 9, 93053 Regensburg, Germany
| | - Martin F. Almstetter
- Institute of Functional Genomics, University of Regensburg, Josef-Engert-Straße 9, 93053 Regensburg, Germany
| | - Magdalena C. Waldhier
- Institute of Functional Genomics, University of Regensburg, Josef-Engert-Straße 9, 93053 Regensburg, Germany
| | - Michael A. Gruber
- Department of Anesthesiology, University Hospital Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany
| | - Nadine Nürnberger
- Institute of Functional Genomics, University of Regensburg, Josef-Engert-Straße 9, 93053 Regensburg, Germany
| | - Peter J. Oefner
- Institute of Functional Genomics, University of Regensburg, Josef-Engert-Straße 9, 93053 Regensburg, Germany
| | - Katja Dettmer
- Institute of Functional Genomics, University of Regensburg, Josef-Engert-Straße 9, 93053 Regensburg, Germany
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Portolés T, Sancho JV, Hernández F, Newton A, Hancock P. Potential of atmospheric pressure chemical ionization source in GC-QTOF MS for pesticide residue analysis. JOURNAL OF MASS SPECTROMETRY : JMS 2010; 45:926-936. [PMID: 20641006 DOI: 10.1002/jms.1784] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The potential applications of a new atmospheric pressure source for GC-MS analysis have been investigated in this work. A list of around 100 GC-amenable pesticides, which includes organochlorine, organophosphorus and organonitrogenated compounds, has been used to evaluate their behavior in the new source. Favoring the major formation of the molecular ion in the source has been the main goal due to the wide-scope screening possibilities that this fact brings in comparison with the traditional, highly fragmented electron ionization spectra. Thus, the addition of water as modifier has been tested as a way to promote the generation of protonated molecules. Pesticides investigated have been classified into six groups according to their ionization/fragmentation behavior. Four of them are characterized by the abundant formation of the protonated molecule in the atmospheric pressure source, mostly being the base peak of the spectrum. These results show that wide-scope screening could be easily performed with this source by investigating the presence of the protonated molecule ion, MH+. The developed procedure has been applied to pesticide screening in different food samples (nectarine, orange and spinach) and it has allowed the presence of several pesticides to be confirmed such as chlorpyriphos ethyl, deltamethrin and endosulfan sulfate. The availability of a quadrupole time-of-flight instrument made it feasible to perform additional MS/MS experiments for both standards and samples to go further in the confirmation of the identity of the detected compounds. Results shown in this paper have been obtained using a prototype source which exhibits promising features that could be applied to other analytical problems apart from those illustrated in this work.
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Affiliation(s)
- T Portolés
- Research Institute for Pesticides and Water, University Jaume I, Castellón 12071, Spain
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Iachetta L, Malek L, Ross BM. The reactions of H(3)O(+), NO(+) and O(2) (+) with several flavourant esters studied using selected ion flow tube mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2010; 24:815-822. [PMID: 20187085 DOI: 10.1002/rcm.4439] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The reactions of H(3)O(+), NO(+), and O(2) (+) with nineteen ester compounds occurring naturally in plants, and having important flavourant properties, were examined using selected ion flow tube mass spectrometry (SIFT-MS). The H(3)O(+) reactions primarily generate [R(1)COOR(2).H](+), and may also produce [R(2)](+) fragment ions and/or fragmentation within the ester linkage. Collisional association/adduct ions, [R(1)COOR(2).NO](+), are the main products formed in the NO(+) reactions, although the carboxyl fragment ion is also detected frequently. The identification of the parent compound may be made more easily in the H(3)O(+) and NO(+) reactions. The inclusion of O(2) (+) reactions in the analysis provides additional information, which may be applied when the identity of a parent compound cannot be determined solely from the H(3)O(+) and NO(+) analysis. Consideration of the product ions generated with the three precursors suggests that SIFT-MS can differentiate between many of the esters investigated, including isomers, although the product ions generated in the reactions with some esters are too similar to allow independent quantification. Our data therefore suggest that SIFT-MS may be a useful tool to rapidly analyse and quantify flavourant esters in complex gas mixtures.
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Affiliation(s)
- Liana Iachetta
- Department of Biology, Lakehead University, 955 Oliver Rd., Thunder Bay, Ontario, P7B 5E1, Canada
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Carrasco-Pancorbo A, Nevedomskaya E, Arthen-Engeland T, Zey T, Zurek G, Baessmann C, Deelder AM, Mayboroda OA. Gas chromatography/atmospheric pressure chemical ionization-time of flight mass spectrometry: analytical validation and applicability to metabolic profiling. Anal Chem 2010; 81:10071-9. [PMID: 19924863 DOI: 10.1021/ac9006073] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Gas Chromatography (GC)-Mass Spectrometry (MS) with Atmospheric Pressure (AP) interface was introduced more than 30 years ago but never became a mainstream technique, mainly because of technical difficulties and cost of instrumentation. A recently introduced multipurpose AP source created the opportunity to reconsider the importance of AP ionization for GC. Here, we present an analytical evaluation of GC/APCI-MS showing the benefits of soft atmospheric pressure chemical ionization for GC in combination with a Time of Flight (TOF) mass analyzer. During this study, the complete analytical procedure was optimized and evaluated with respect to characteristic analytical parameters, such as repeatability, reproducibility, linearity, and detection limits. Limits of detection (LOD) were found within the range from 11.8 to 72.5 nM depending on the type of compound. The intraday and interday repeatability tests demonstrate relative standard deviations (RSDs) of peak areas between 0.7%-2.1% and 3.8%-6.4% correspondingly. Finally, we applied the developed method to the analysis of human cerebrospinal fluid (CSF) samples to check the potential of this new analytical combination for metabolic profiling.
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Ray AD, Hammond J, Major H. Molecular ions and protonated molecules observed in the atmospheric solids analysis probe analysis of steroids. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2010; 16:169-174. [PMID: 20212333 DOI: 10.1255/ejms.1069] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Atmospheric pressure chemical ionisation (APCI) has often been used to ionise steroids in mass spectrometry, usually when interfaced to high-performance liquid chromatography (HPLC). However, in positive ion mode, a dehydrated protonated molecule is often observed with a loss of structural information. The recently introduced technique of atmospheric solids analysis probe (ASAP) has the advantage that the sample can be analysed directly and does not need to be interfaced to HPLC. Existing ionisation sources such as direct analysis in real time (DART) and desorption electrospray ionisation (DESI) have shown the advantage of direct analysis techniques in a variety of applications. ASAP can be performed on commercial atmospheric pressure ionisation (API) mass spectrometers with only simple modifications to API sources. The samples are vaporised by hot nitrogen gas from the electrospray desolvation heater and ionised by a corona discharge. A range of commercially available steroids were analysed by ASAP to investigate the mechanism of ionisation. ASAP analysis of steroids generally results in the formation of the parent molecular ion as either the radical cation M+* or the protonated molecule MH+. The formation of the protonated molecule is a result of proton transfer from ionised water clusters in the source. However, if the source is dry, then formation of the radical cation is the primary ionisation mechanism.
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Affiliation(s)
- Andrew D Ray
- Deptartment of Analytical Development, AstraZeneca, Loughborough, Leicestershire LE11 5RH, UK.
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Gelpí E. From large analogical instruments to small digital black boxes: 40 years of progress in mass spectrometry and its role in proteomics. Part I 1965-1984. JOURNAL OF MASS SPECTROMETRY : JMS 2008; 43:419-435. [PMID: 18338320 DOI: 10.1002/jms.1403] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
As the title implies, the author undertakes a personal retrospective on the developments that since 1965 have shaped MS and taken it from a position of simply playing a role in protein chemistry to becoming an indispensable tool in proteomics, all in the past 40-year span. The article reviews the MS timeline of events, stopping at various time points where MS made significant contributions to protein chemistry or where the development of new instrumentation for MS represented a major advance for peptide and protein work. Major highlights in the field and their significance for peptide and protein characterization are covered, starting from the pioneering work carried out in the 1960s on peptide derivative formation and sequencing with instrumentation proper of that time, to later work done with triple, quad, and four-sector instruments, and on to the more recent work on the characterization of the proteome with ion traps, time-of-flight (TOF) instruments, and new ionization and tagging techniques.
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Affiliation(s)
- Emilio Gelpí
- Instituto de Investigaciones Biomédicas de Barcelona, CSIC-IDIBAPS, Roselló 161, Barcelona, Spain.
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Randall LG. The Present Status of Dense (Supercritical) Gas Extraction and Dense Gas Chromatography: Impetus for DGC/MS Development. SEP SCI TECHNOL 2006. [DOI: 10.1080/01496398208058142] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- L. G. Randall
- a Department of Chemistry , University of Utah , Salt Lake City , Utah , 84112 , United States
- b Hewlett-Packard, Avondale Division , Avondale , PA , 19311
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Lou MF, Hamilton PB. Separation and quantitation of peptides and amino acids in normal human urine. METHODS OF BIOCHEMICAL ANALYSIS 2006; 25:203-71. [PMID: 372735 DOI: 10.1002/9780470110454.ch3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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McEwen CN, McKay RG. A combination atmospheric pressure LC/MS:GC/MS ion source: advantages of dual AP-LC/MS:GC/MS instrumentation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2005; 16:1730-8. [PMID: 16185892 DOI: 10.1016/j.jasms.2005.07.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Revised: 07/06/2005] [Accepted: 07/06/2005] [Indexed: 05/04/2023]
Abstract
Modification of commercial LC/MS instrumentation to allow both atmospheric pressure (AP) LC/MS and GC/MS is described. Advantages of this additional capability versus LC/MS alone include higher chromatographic resolution in the GC versus LC mode, greater peak capacity for complex mixture analysis, higher sensitivity for a variety of volatile compounds, and the ability to observe compounds of low polarity that are not readily observed in LC/MS. Advantages over conventional GC/MS include the ability to use higher carrier gas flow and shorter columns for passing less volatile materials through the gas chromatograph, selective ionization, and rapid switching between positive and negative ion modes. Other advantages include application of the enhanced capabilities of LC/MS instrumentation to GC/MS analyses such as cone voltage fragmentation, MS(n), high mass resolution, and accurate mass measurement. Limitations of APGC/MS include the inability to observe saturated hydrocarbon and certain other highly nonpolar compounds and less odd-electron fragmentation for computer aided library searching. For some analyses, the limitation related to ionization of highly nonpolar compounds is advantageous, as is the simplified mass spectrum and easy molecular weight identification that results from less fragmentation observed in the AP ionization mode.
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Affiliation(s)
- Charles N McEwen
- Central Research & Development Department, DuPont Corporate Center for Analytical Sciences, PO Box 80228, Wilmington, DE 19880-0228, USA.
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Games DE. Combined high performance liquid chromatography mass spectrometry. BIOMEDICAL MASS SPECTROMETRY 1981; 8:454-62. [PMID: 7306684 DOI: 10.1002/bms.1200080919] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Combined gas chromatography mass spectrometry, because of its ability to provide both high sensitivity and specificity, has become a vital technique for the identification and quantitation of natural and synthetic chemicals in a wide variety of areas. Unfortunately, a very large number of organic compounds are not directly amenable to gas chromatography since they are thermally labile and/or of low volatility. Chemical modification of compounds of interest can assist in some cases, but it is not universally applicable. High performance liquid chromatography has been increasingly utilized for studies of compounds of these types since heat is not usually involved in the analysis. Combined liquid chromatography mass spectrometry would lend a new dimension to these studies, enabling the separating ability of the liquid chromatograph to be combined with the sensitivity and specificity of the mass spectrometer. Approaches to liquid chromatography mass spectrometry are discussed. Using examples from our liquid chromatographic mass spectrometric studies of natural compounds, drugs and pesticides, the current abilities of such systems to identify and quantify natural and synthetic chemicals present in a complex matrix of other chemicals are described.
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Games DE, Lewis E. Combined liquid chromatography mass spectrometry of glycosides, glucuronides, sugars and nucleosides. ACTA ACUST UNITED AC 1980. [DOI: 10.1002/bms.1200071006] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Jellum E. Profiling of human body fluids in healthy and diseased states using gas chromatography and mass spectrometry, with special reference to organic acids. JOURNAL OF CHROMATOGRAPHY 1977; 143:427-62. [PMID: 330556 DOI: 10.1016/s0378-4347(00)81792-2] [Citation(s) in RCA: 189] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review summarizes recent advances in the application of gas chromatography and mass spectrometry to the study of human diseases. Emphasis is placed upon the organic acid profiles of the various body fluids. Methods for sample work-up prior to separation and mass spectrometric analysis are reviewed, and artifacts and pitfalls are discussed. Organic acid profiles, obtained with packed or capillary columns attached to mass spectrometers with or without computer systems, have led to the discovery of new normal metabolites, new metabolic disorders, and to new knowledge about a number of other diseases. Stable isotopes and gas chromatography--mass spectrometry are suitable for quantitative analysis of many compounds in the body fluids, and well suited for investigation of metabolic pathways.
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