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Ding X, Liu K, Shi Z. LASER DESORPTION/ABLATION POSTIONIZATION MASS SPECTROMETRY: RECENT PROGRESS IN BIOANALYTICAL APPLICATIONS. Mass Spectrom Rev 2021; 40:566-605. [PMID: 32770707 DOI: 10.1002/mas.21649] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/07/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
Lasers have long been used in the field of mass spectrometric analysis for characterization of condensed matter. However, emission of neutrals upon laser irradiation surpasses the number of ions. Typically, only one in about one million analytes ejected by laser desorption/ablation is ionized, which has fueled the quest for postionization methods enabling ionization of desorbed neutrals to enhance mass spectrometric detection schemes. The development of postionization techniques can be an endeavor that integrates multiple disciplines involving photon energy transfer, electrochemistry, gas discharge, etc. The combination of lasers of different parameters and diverse ion sources has made laser desorption/ablation postionization (LD/API) a growing and lively research community, including two-step laser mass spectrometry, laser ablation atmospheric pressure photoionization mass spectrometry, and those coupled to ambient mass spectrometry. These hyphenated techniques have shown potentials in bioanalytical applications, with major inroads to be made in simultaneous location and quantification of pharmaceuticals, toxins, and metabolites in complex biomatrixes. This review is intended to provide a timely comprehensive view of the broadening bioanalytical applications of disparate LD/API techniques. We also have attempted to discuss these applications according to the classifications based on the postionization methods and to encapsulate the latest achievements in the field of LD/API by highlighting some of the very best reports in the 21st century. © 2020 John Wiley & Sons Ltd.
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Affiliation(s)
- Xuelu Ding
- Department of Pharmaceutical Analysis, School of Pharmacy, Qingdao University, Qingdao, 266021, China
| | - Kun Liu
- Department of Pharmaceutical Analysis, School of Pharmacy, Qingdao University, Qingdao, 266021, China
| | - Zhenyan Shi
- Department of Pharmaceutical Analysis, School of Pharmacy, Qingdao University, Qingdao, 266021, China
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Yang E, Fournelle F, Chaurand P. Silver spray deposition for AgLDI imaging MS of cholesterol and other olefins on thin tissue sections. J Mass Spectrom 2020; 55:e4428. [PMID: 31410898 DOI: 10.1002/jms.4428] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 07/26/2019] [Accepted: 08/05/2019] [Indexed: 06/10/2023]
Abstract
Olefins such as cholesterol and unsaturated fatty acids play important biological roles. Silver-assisted laser desorption ionization (AgLDI) takes advantage of the strong affinity of silver to conjugate with double bonds to selectively ionize these molecules for imaging mass spectrometry (IMS) experiments. For IMS studies, two main approaches for silver deposition have been described in the literature: fine coating by silver sputtering and spray deposition of silver nanoparticles. While these approaches allow for extremely high resolution IMS experiments to be conducted, they are not readily available to all laboratories. Herein, we present a silver nitrate spray deposition approach as an alternative to silver sputtering and nanoparticle deposition for routine IMS analysis. The silver nitrate spray has the same level of specificity and sensitivity for olefins, particularly cholesterol, and has shown to be capable of IMS experiments down to 10-μm spatial resolution. Minimal sample preparation and the affordability of silver nitrate make this a convenient and accessible technique worth considering.
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Affiliation(s)
- Ethan Yang
- Department of Chemistry, University of Montreal, Montreal, Quebec, Canada, H3C 3J7
| | - Frédéric Fournelle
- Department of Chemistry, University of Montreal, Montreal, Quebec, Canada, H3C 3J7
| | - Pierre Chaurand
- Department of Chemistry, University of Montreal, Montreal, Quebec, Canada, H3C 3J7
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Zhang T, Li ZY, Liu QY, He SG. Chemical Ionization of Large Linear Alkanes and Small Oxidized Volatile Organic Compounds by the Reactions with Atomic Gold Cations. Anal Chem 2017; 89:9083-9090. [DOI: 10.1021/acs.analchem.7b01791] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ting Zhang
- State Key Laboratory
for Structural Chemistry of Unstable and Stable Species, CAS Research/Education
Center for Excellence in Molecular Sciences, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, People’s Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Zi-Yu Li
- State Key Laboratory
for Structural Chemistry of Unstable and Stable Species, CAS Research/Education
Center for Excellence in Molecular Sciences, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, People’s Republic of China
| | - Qing-Yu Liu
- State Key Laboratory
for Structural Chemistry of Unstable and Stable Species, CAS Research/Education
Center for Excellence in Molecular Sciences, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, People’s Republic of China
| | - Sheng-Gui He
- State Key Laboratory
for Structural Chemistry of Unstable and Stable Species, CAS Research/Education
Center for Excellence in Molecular Sciences, Institute
of Chemistry, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, People’s Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
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Schnapp A, Niehoff AC, Koch A, Dreisewerd K. Laser desorption/ionization mass spectrometry of lipids using etched silver substrates. Methods 2016; 104:194-203. [DOI: 10.1016/j.ymeth.2016.01.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/13/2016] [Accepted: 01/25/2016] [Indexed: 10/22/2022] Open
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Jin D, Su Y, Lee YI. Analysis of Benzanthrone in Urban Surface Soil Using Laser Desorption/Ferric Chloride Chemical Ionization Time-of-Flight Mass Spectrometry. B KOREAN CHEM SOC 2015. [DOI: 10.1002/bkcs.10522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Dongri Jin
- Key Laboratory of Nature Resource of Changbai Mountain and Functional Molecules; Ministry of Education, Yanbian University; Yanji 133002 China
| | - Yujia Su
- Key Laboratory of Nature Resource of Changbai Mountain and Functional Molecules; Ministry of Education, Yanbian University; Yanji 133002 China
| | - Yong-Ill Lee
- Department of Chemistry; Changwon National University; Changwon 641-773 Republic of Korea
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Bartkowiak G, Gawron K, Jurga S, Schroeder G. Mass spectrometry of lanthanide(III) complexes with 2,6-diformylpyridine bis(4-pyridylcarbohydrazone) and its unusual methylation observed in matrix-assisted laser desorption/ionization mass spectra. Rapid Commun Mass Spectrom 2015; 29:1696-1702. [PMID: 26467121 DOI: 10.1002/rcm.7260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Revised: 06/12/2015] [Accepted: 06/21/2015] [Indexed: 06/05/2023]
Affiliation(s)
- Grażyna Bartkowiak
- Faculty of Chemistry, Adam Mickiewicz University in Poznań, Umultowska 89B, 61-614, Poznań, Poland
- NanoBioMedical Centre, Adam Mickiewicz University in Poznań, Umultowska 85, 61-614, Poznań, Poland
| | - Katarzyna Gawron
- Faculty of Chemistry, Adam Mickiewicz University in Poznań, Umultowska 89B, 61-614, Poznań, Poland
| | - Stefan Jurga
- NanoBioMedical Centre, Adam Mickiewicz University in Poznań, Umultowska 85, 61-614, Poznań, Poland
- Faculty of Physics, Adam Mickiewicz University in Poznań, Umultowska 85, 61-614, Poznań, Poland
| | - Grzegorz Schroeder
- Faculty of Chemistry, Adam Mickiewicz University in Poznań, Umultowska 89B, 61-614, Poznań, Poland
- NanoBioMedical Centre, Adam Mickiewicz University in Poznań, Umultowska 85, 61-614, Poznań, Poland
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Smolira A, Wessely-Szponder J. Importance of the matrix and the matrix/sample ratio in MALDI-TOF-MS analysis of cathelicidins obtained from porcine neutrophils. Appl Biochem Biotechnol 2014; 175:2050-65. [PMID: 25432341 PMCID: PMC4322226 DOI: 10.1007/s12010-014-1405-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 11/13/2014] [Indexed: 11/24/2022]
Abstract
Qualitative and quantitative mass spectrometric studies of biomolecules for example proteins, peptides, or lipids contained in biological samples like physiologic fluids are very important for many fields of science such as medicine, veterinary medicine, biology, biochemistry, molecular biology, or environmental sciences. In the last two decades, MALDI TOF MS — matrix-assisted laser desorption mass spectrometry, proved to be an especially convenient tool for these analyses. The main advantages of this method are its rapidity and high sensitivity which is particularly appreciated in the case of studies of complex biological specimen. A major challenge for many researchers is to maximize this sensitivity, among others, by appropriate procedures of sample preparation for the measurement. The objective of this work was to optimize these procedures, selecting the optimal matrix and optimum proportions of the sample and the matrix solution in a mixture of both solutions, aiming at the achievement of the maximum intensity of ion current. In this respect, five low molecular mass cathelicidins were studied: prophenin-2, protegrins 1–3, PR-39. All of them were obtained directly from the porcine blood. As a result of studies, the authors determined such experimental conditions when the intensity of investigated ionic current had the highest value.
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Affiliation(s)
- Anna Smolira
- Department of Molecular Physics, Institute of Physics, Maria Curie Sklodowska University, Pl. M. Curie-Skłodowskiej 1, 20-031, Lublin, Poland,
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9
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Zhou X, Shi Q, Zhang Y, Zhao S, Zhang R, Chung KH, Xu C. Analysis of Saturated Hydrocarbons by Redox Reaction with Negative-Ion Electrospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry. Anal Chem 2012; 84:3192-9. [DOI: 10.1021/ac203035k] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Xibin Zhou
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 China
| | - Yahe Zhang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 China
| | - Suoqi Zhao
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 China
| | - Rui Zhang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 China
| | - Keng H. Chung
- Well Resources Inc., 3919-149A Street, Edmonton, Alberta, Canada T6R
1J8
| | - Chunming Xu
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 China
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Suarez E, Nguyen HP, Ortiz IP, Lee KJ, Kim SB, Krzywinski J, Schug KA. Matrix-assisted laser desorption/ionization-mass spectrometry of cuticular lipid profiles can differentiate sex, age, and mating status of Anopheles gambiae mosquitoes. Anal Chim Acta 2011; 706:157-63. [PMID: 21995923 DOI: 10.1016/j.aca.2011.08.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 08/23/2011] [Accepted: 08/24/2011] [Indexed: 11/25/2022]
Abstract
Malaria is a devastating mosquito-borne disease, which affects hundreds of millions of people each year. It is transmitted predominantly by Anopheles gambiae, whose females must be >10 days old to become infective. In this study, cuticular lipids from a laboratory strain of this mosquito species were analyzed using a mass spectrometry method to evaluate their utility for age, sex and mating status differentiation. Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS), in conjunction with an acenaphthene/silver nitrate matrix preparation, was shown to be 100% effective in classifying A. gambiae females into 1, 7-10, and 14 days of age. MALDI-MS analysis, supported by multivariate statistical methods, was also effective in detecting cuticular lipid differences between the sexes and between virgin and mated females. The technique requires further testing, but the obtained results suggest that MALDI-MS cuticular lipid spectra could be used for age grading of A. gambiae females with precision greater than with other available methods.
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Affiliation(s)
- Estrella Suarez
- Department of Chemistry & Biochemistry, The University of Texas at Arlington, Arlington, TX, United States
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Leiterer J, Panne U, Thünemann AF, Weidner SM. Container-less polymerization in acoustically levitated droplets: an analytical study by GPC and MALDI-TOF mass spectrometry. Anal Methods 2011; 3:70-73. [PMID: 32938112 DOI: 10.1039/c0ay00390e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Molecular masses and end groups of polystyrene (PS) formed in a novel container-less polymerization strategy, based on levitated droplets in an acoustic trap, were determined by Gel Permeation Chromatography (GPC) and Matrix-assisted Laser Desorption/Ionization Time of Flight Mass spectrometry (MALDI-TOF MS).
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Affiliation(s)
- Jork Leiterer
- BAM Bundesanstalt für Materialforschung und -prüfung, Richard-Willstätter-Str. 11, 12489, Berlin, Germany.
| | - Ulrich Panne
- BAM Bundesanstalt für Materialforschung und -prüfung, Richard-Willstätter-Str. 11, 12489, Berlin, Germany.
- Humboldt-Universitaet zu Berlin, Department of Chemistry, Brook-Taylor-Strasse 2, 12489, Berlin, Germany
| | - Andreas F Thünemann
- BAM Bundesanstalt für Materialforschung und -prüfung, Richard-Willstätter-Str. 11, 12489, Berlin, Germany.
| | - Steffen M Weidner
- BAM Bundesanstalt für Materialforschung und -prüfung, Richard-Willstätter-Str. 11, 12489, Berlin, Germany.
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12
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Hart-Smith G, Barner-Kowollik C. Contemporary Mass Spectrometry and the Analysis of Synthetic Polymers: Trends, Techniques and Untapped Potential. MACROMOL CHEM PHYS 2010. [DOI: 10.1002/macp.201000107] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Jun JH, Song Z, Liu Z, Nikolau BJ, Yeung ES, Lee YJ. High-spatial and high-mass resolution imaging of surface metabolites of Arabidopsis thaliana by laser desorption-ionization mass spectrometry using colloidal silver. Anal Chem 2010; 82:3255-65. [PMID: 20235569 DOI: 10.1021/ac902990p] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
High-spatial resolution and high-mass resolution techniques are developed and adopted for the mass spectrometric imaging of epicuticular lipids on the surface of Arabidopsis thaliana. Single cell level spatial resolution of approximately 12 mum was achieved by reducing the laser beam size by using an optical fiber with 25 mum core diameter in a vacuum matrix-assisted laser desorption ionization-linear ion trap (vMALDI-LTQ) mass spectrometer and improved matrix application using an oscillating capillary nebulizer. Fine chemical images of a whole flower were visualized in this high spatial resolution showing substructure of an anther and single pollen grains at the stigma and anthers. The LTQ-Orbitrap with a MALDI ion source was adopted to achieve MS imaging in high mass resolution. Specifically, isobaric silver ion adducts of C29 alkane (m/z 515.3741) and C28 aldehyde (m/z 515.3377), indistinguishable in low-resolution LTQ, can now be clearly distinguished and their chemical images could be separately constructed. In the application to roots, the high spatial resolution allowed molecular MS imaging of secondary roots and the high mass resolution allowed direct identification of lipid metabolites on root surfaces.
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Affiliation(s)
- Ji Hyun Jun
- Ames Laboratory, U.S. Department of Energy, Ames, Iowa 50011, USA
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14
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Abstract
A molecular solid of fullerene (C(60)) intercalated with cobalt cyclopentadienyl dicarbonyl (CoCp(CO)(2)) was shown to be an effective matrix for matrix-assisted laser desorption/ionization mass spectrometry (MALDI) of large alkanes (demonstrated up to C(94)H(190)) and polyethylenes that otherwise cannot be produced as intact ions in the gas phase.
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Affiliation(s)
- William E Wallace
- Polymers Division, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8541, Gaithersburg, MD 20899-8541, USA.
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Jaber AJ, Wilkins CL. Hydrocarbon polymer analysis by external MALDI fourier transform and reflectron time of flight mass spectrometry. J Am Soc Mass Spectrom 2005; 16:2009-16. [PMID: 16246576 DOI: 10.1016/j.jasms.2005.08.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Revised: 07/20/2005] [Accepted: 08/16/2005] [Indexed: 05/05/2023]
Abstract
The traditional solvent-based matrix-assisted laser desorption ionization (MALDI) preparation method has been used to analyze nonpolar polymers of various molecular weights. High resolution silver cationized oligomers with masses of up to 12 KDa were measured using 9.4 tesla Fourier transform mass spectrometry (FTMS) with an external ionization source. It was observed that when time-of-flight mass spectrometry was used, the spectra of polyethylene polymers showed abundant low mass fragment ions. However, these fragments were absent from the FTMS spectra.
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Affiliation(s)
- Arwah J Jaber
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, 72701, USA
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Maziarz III EP, Baker GA, Wood TD. Electrospray ionization Fourier transform mass spectrometry of polycyclic aromatic hydrocarbons using silver(I)-mediated ionization. CAN J CHEM 2005. [DOI: 10.1139/v05-195] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Here, a methodology employing doped Ag(I) salt as an in situ cationization reagent for efficient ionization of nonpolar molecules within a conventional electrospray ionization source is described. The effectiveness of Ag(I)-mediated ionization is demonstrated using ESI Fourier transform mass spectrometry for the rapid detection and identification of priority pollutant polyaromatic hydrocarbon (PAH) species. In contrast to earlier coordination ESI-MS reports employing silver salts, argentated species are not typically observed for PAH species. Instead, oxidation of the PAH occurs to produce only the [PAH]+· odd-electron molecular parent ion, simplifying spectral analysis. In addition, the method demonstrates linear quantitative performance. The Ag(I) reagent provides quantifiable PAHs (not ordinarily amenable to ESI-MS) from 64 ppb, and suggests the immediate potential for sampling and on-line monitoring of complex, real world, and otherwise intractable environmental samples. Finally, the high mass accuracy of ESI Fourier transform mass spectrometry further allows unequivocal identification of molecular formulas within PAH mixtures.Key words: electrospray ionization, nonpolar, hydrocarbons, polyaromatic, Fourier transform mass spectrometry.
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Grace LI, Abo-Riziq A, deVries MS. An in situ silver cationization method for hydrocarbon mass spectrometry. J Am Soc Mass Spectrom 2005; 16:437-440. [PMID: 15792711 DOI: 10.1016/j.jasms.2004.12.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2004] [Revised: 12/20/2004] [Accepted: 12/23/2004] [Indexed: 05/24/2023]
Abstract
We have developed a novel cationization method for the analysis of long-chain hydrocarbons via UV laser desorption mass spectrometry. In this technique we electrospray a thin coating of AgNO3 over a sample and perform UV laser desorption to produce Ag+ cationization of sample molecules. Use of this technique in our microscope/TOF-MS allows us to determine the spatial distribution of the species we detect in the sample. We demonstrate 8-mu spatial resolution, and submicron resolution is possible in principle. In mixed samples containing aromatic and aliphatic compounds, the aromatic compounds ionize directly and do not form adducts, and thus give single peaks as opposed to doublets from silver cations. This enables distinction between aromatic and aliphatic compounds that are in the same sample.
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Affiliation(s)
- Louis I Grace
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93117-9510, USA
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Di Croce PG, Aubriet F, Chéty-Gimondo R, Muller JF, Grange P. Characterization of a model Phillips catalyst by mass spectrometry. Rapid Commun Mass Spectrom 2004; 18:601-608. [PMID: 15052569 DOI: 10.1002/rcm.1375] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A model Phillips catalyst for ethylene polymerization, prepared by spin coating a Cr(III)(Cr(acac)3) precursor on a silicon wafer, was submitted to an oxidative activation. Laser ablation Fourier transform mass spectrometry provided direct information on molecular species at the silicon wafer surface during activation. At 350 degrees C the chromium precursor was degraded, while chromium oxide species were formed. The chromium concentration decreased with temperature. The activated model catalyst was active for ethylene polymerization. Using complementary techniques (Fourier transform infrared spectroscopy, laser desorption/ionization mass spectrometry), the polymer was identified as crystalline polyethylene. After 1 h of polymerization at 160 degrees C, dome-like structures were observed by atomic force microscopy. Their morphologies were constituted of regions of parallel aligned lamellae of polymer.
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Affiliation(s)
- Pascal Gabriel Di Croce
- Unité de catalyse et de chimie des matériaux divisés, Université catholique de Louvain, Croix du Sud 2/17, B-1348 Louvain-la-Neuve, Belgium.
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Byrd HCM, Guttman CM, Ridge DP. Molecular mass determination of saturated hydrocarbons: reactivity of eta5-cyclopentadienylcobalt ion (CpCo*+) and linear alkanes up to C-30. J Am Soc Mass Spectrom 2003; 14:51-57. [PMID: 12504333 DOI: 10.1016/s1044-0305(02)00815-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The present study demonstrates the feasibility of the eta5-cyclopentadienylcobalt ion (CpCo*+) as a suitable cationization reagent for saturated hydrocarbon analysis by mass spectrometry. Ion/molecule reactions of CpCo*+ and three medium chain-length n-alkanes were examined using Fourier-transform ion cyclotron resonance mass spectrometry. Second-order rate constants and reaction efficiencies were determined for the reactions studied. Loss of two hydrogen molecules from the CpCo-alkane ion complex was found to dominate all reactions ( > or = 80%). Furthermore, this dehydrogenation reaction efficiency increases with increasing chain length. These preliminary results suggest that the CpCo*+ ion may be a promising cationization reagent of longer chain saturated hydrocarbons and polyolefins.
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Affiliation(s)
- H C Michelle Byrd
- National Institute of Standards and Technology, Polymers Division, Gaithersburg, Maryland 20899, USA.
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Yalcin T, Wallace WE, Guttman CM, Li L. Metal powder substrate-assisted laser desorption/ionization mass spectrometry for polyethylene analysis. Anal Chem 2002; 74:4750-6. [PMID: 12349979 DOI: 10.1021/ac0256641] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Polyethylene is one of the most important industrial polymers and is also one of the most challenging polymers to be characterized by mass spectrometry. We have developed a substrate-assisted laser desorption/ionization (LDI) mass spectrometric method for polyethylene analysis. In this method, cobalt, copper, nickel, or iron metal powders are used as a sample substrate and silver nitrate is used as the cationization reagent. Using a conventional UV LDI time-of-flight mass spectrometer, intact oligomer ions having masses up to 5000 u can be detected. Cobalt is found to produce spectra with the highest signal-to-noise ratio and the lowest level of fragmentation. Cobalt powder size is shown to have some effect on the spectra produced. The best results are obtained with the use of cobalt powders with diameters ranging from 30 to 100 microm. Fragmentation cannot be totally eliminated, but the fragment ion peaks can be readily discerned from the intact polyethylene ions in the substrate-assisted LDI spectrum. Thus, the average molecular masses of low-mass polyethylene samples can be determined by using this method. A rapid heating model is used to account for the effectiveness of using the coarse metal powders to assist the analysis of intact polyethylene molecules by LDI.
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Affiliation(s)
- Talat Yalcin
- Department of Chemistry, University of Alberta, Edmonton, Canada
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Chen R, Yalcin T, Wallace WE, Guttman CM, Li L. Laser desorption ionization and MALDI time-of-flight mass spectrometry for low molecular mass polyethylene analysis. J Am Soc Mass Spectrom 2001; 12:1186-1192. [PMID: 11720394 DOI: 10.1016/s1044-0305(01)00308-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Polyethylene's inert nature and difficulty to dissolve in conventional solvents at room temperature present special problems for sample preparation and ionization in mass spectrometric analysis. We present a study of ionization behavior of several polyethylene samples with molecular masses up to 4000 Da in laser desorption ionization (LDI) time-of-flight mass spectrometers equipped with a 337 nm laser beam. We demonstrate unequivocally that silver or copper ion attachment to saturated polyethylene can occur in the gas phase during the UV LDI process. In LDI spectra of polyethylene with molecular masses above approximately 1000 Da, low mass ions corresponding to metal-alkene structures are observed in addition to the principal distribution. By interrogating a well-characterized polyethylene sample and a long chain alkane, C94H190, these low mass ions are determined to be the fragmentation products of the intact metal-polyethylene adduct ions. It is further illustrated that fragmentation can be reduced by adding matrix molecules to the sample preparation.
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Affiliation(s)
- R Chen
- Department of Chemistry, University of Alberta, Edmonton, Canada
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Abstract
Understanding metal ion interactions with long-chain alkanes not only is of fundamental importance in the areas of organometallic chemistry, surface chemistry, and catalysis, but also has significant implication in mass spectrometry method development for the analysis of polyethylene. Polyethylene represents one of the most challenging classes of polymers to be analyzed by mass spectrometry. In this work, reactions of several transition-metal ions including Cr+, Mn+, Fe+, Co+, Ni+, Cu+, and Ag+ with long-chain alkanes, C28H58 and C36H74, are reported. A metal powder and the nonvolatile alkane are co-deposited onto a sample target of a laser desorption/ionization (LDI) time-of-flight mass spectrometer. The metal ions generated by LDI react with the vaporized alkane during desorption. It is found that all these metal ions can form adduct ions with the long-chain alkanes. Fe+, Co+, and Ni+ produce in-source fragment ions resulting from dehydrogenation and dealkylation of the adduct ions. The post-source decay (PSD) spectra of the metal-alkane adduct ions are recorded. It is shown that PSD of Ag+ alkane adduct ions produces bare metal ions only, suggesting weak binding between this metal ion and alkane. The PSD spectra of the Fe+, Co+, and Ni+ alkane adduct ions display extensive fragmentation. Fragment ions are also observed in the PSD spectra of Cr+, Mn+, and Cu+ alkane adduct ions. The high reactivity of Fe+, Co+, and Ni+ is consistent with that observed in small alkane systems. The unusually high reactivity of Cr+, Mn+, and Cu+ is rationalized by a reaction scheme where a long-chain alkane first forms a complex with a metal ion via ion/induced dipole interactions. If sufficient internal energy is gained during the complex formation, metal ions can be inserted into C-H and C-C bonds of the alkane, followed by fragmentation. The thermal energy of the neutral alkane is believed to be the main source of the internal energy acquired in the complex. Finally, the implication of this work on mass spectrometry method development for polyethylene analysis is discussed.
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Affiliation(s)
- R Chen
- Department of Chemistry, University of Alberta, Edmonton, Canada
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Macha SF, Limbach PA, Savickas PJ. Application of nonpolar matrices for the analysis of low molecular weight nonpolar synthetic polymers by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. J Am Soc Mass Spectrom 2000; 11:731-737. [PMID: 10937796 DOI: 10.1016/s1044-0305(00)00137-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The application of nonpolar matrices for the analysis of low molecular weight nonpolar synthetic polymers using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is demonstrated. Anthracene, pyrene, and acenaphthene were utilized as nonpolar matrices for the analysis of polybutadiene, polyisoprene, and polystyrene samples of various average molecular weights ranging from about 700 to 5,000. The standard MALDI-MS approach for the analysis of these types of polymers involves the use of conventional acidic matrices, such as all-trans-retinoic acid, with an additional cationization reagent. The nonpolar matrices used in this study are shown to be as equally effective as the conventional matrices. The uniform mixing of the nonpolar matrices and the nonpolar analytes enhances the MALDI-MS spectral reproducibility. Silver salts were found to be the best cationization reagents for all of the cases studied. Copper salts worked well for polystyrene, poorly for polyisoprene, and not at all for polybutadiene samples. These matrices should be useful for the characterization of hydrocarbon polymers and other analytes, such as modified polymers, which may potentially be sensitive to acidic matrices.
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Affiliation(s)
- SF Macha
- Department of Chemistry, Louisiana State University, Baton Rouge 70803, USA
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Molander P, Ommundsen E, Greibrokk T. Separation of technical waxes by temperature-programmed packed-capillary liquid chromatography. Chromatographia 2000. [DOI: 10.1007/bf02490615] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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27
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Abstract
A laser desorption/ionization (LDI) time-of-flight mass spectrometric (TOF-MS) technique was used for the molecular mass analysis of thia fatty acids and esters, samples without appreciable light absorption at the laser wavelength. After a sample overlayer is deposited by solvent evaporation on a thin silver film substrate, it is subjected to 355 or 532 nm Nd : YAG laser irradiation. Photoablation of the Ag film substrate occurs with sufficient laser fluence, producing silver cluster cations, which can react with the desorbed thia fatty acid or ester molecules in the gas phase. Silver cation attachment of thia fatty esters may produce a silver-cationized analyte and fragments of structural diagnostic value, whereas thia fatty acids would not. With oxygen(s) present on the sulfur in sulfoxy fatty acids and esters, a silver-cationized analyte and additional fragments are produced. Formation of these fragments is consistent with charge-remote mechanisms through simple cleavage and rearrangement pathways. The structural reactivity of these compounds with ablated silver cations is hence comprehensively analyzed.
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Affiliation(s)
- S Owega
- Ottawa-Carleton Chemistry Institute, Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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Abstract
This tutorial discusses the predominant methods available for surface mass spectrometry (MS) of molecular species: thermal desorption spectroscopy, laser desorption MS, secondary ion MS, post-ionization of desorbed neutrals and surface matrix-assisted laser desorption/ionization. Each of these has the capability to analyze molecular species that are chemisorbed, physisorbed, covalently bound to or the predominant component of a solid surface. These surface MS methods are briefly described, then their capabilities demonstrated using data predominantly from the authors' work. Comparisons are made with related methods in conventional MS. A very brief discussion is provided on the importance of complementing surface MS data with data from x-ray photoelectron spectroscopy and other surface analysis tools.
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Affiliation(s)
- L Hanley
- Department of Chemistry, m/c 111, University of Illinois at Chicago, 845 W. Taylor St., 4500 SES, Chicago, Illinois 60607-7061, USA.
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Yao J, Scott JR, Young MK, Wilkins CL. Importance of matrix:analyte ratio for buffer tolerance using 2,5-dihydroxybenzoic acid as a matrix in matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry and matrix-assisted laser desorption/ionization-time of flight. J Am Soc Mass Spectrom 1998; 9:805-13. [PMID: 9692253 DOI: 10.1016/s1044-0305(98)00046-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Many biological samples destined for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) contain buffers. The presence of these buffers often inhibits the ability to obtain spectra. Here, the results of a study of the effects of six different buffers on spectra of three representative small proteins are reported utilizing 2,5-dihydroxybenzoic acid as matrix. These proteins, bovine insulin, cytochrome c, and bovine albumin have masses from approximately 5000 to 66,000 Da. Three different sample preparation techniques were investigated: aerospray, dried-drop, and acetone redeposition. Both MALDI Fourier transform and time-of-flight mass spectrometry results show that buffer tolerance of MALDI-MS samples depends upon several factors, including the relative amount of the buffer in the MALDI matrix, as well as the identity of the specific buffer. Furthermore, the rate at which buffer tolerance decreases as buffer concentration is increased varies from buffer to buffer. The current results reveal that, at very high matrix:analyte ratios, buffer tolerance of MALDI is dramatically greater than concluded in previous literature reports.
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Affiliation(s)
- J Yao
- Department of Chemistry, University of California, Riverside, USA
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Arnim Cumme G, Blume E, Bublitz R, Hoppe H, Horn A. Composition analysis of detergents of the polyoxyethylene type: comparison of thin-layer chromatography, reversed-phase chromatography and matrix-assisted laser desorption/ionization mass spectrometry. J Chromatogr A 1997; 791:245-53. [DOI: 10.1016/s0021-9673(97)00800-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Wu Z, Biemann K. The maldi mass spectra of carbosilane-based dendrimers containing up to eight fixed positive or 16 negative charges. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0168-1176(97)00157-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Pasch H, Deffieux A, Ghahary R, Schapacher M, Rique-Lurbet L. Analysis of Macrocyclic Polystyrenes. 2. Mass Spectrometric Investigations. Macromolecules 1997. [DOI: 10.1021/ma960916j] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Harald Pasch
- Deutsches Kunststoff-Institut, Schlossgartenstrasse 6, 64289 Darmstadt, Germany, and Laboratoire de Chìmie des Polymeres Organiques, ENSCPB, Universite Bordeaux-1, 351 cours de la Liberation, 33405 Talence-Cedex, France
| | - Alain Deffieux
- Deutsches Kunststoff-Institut, Schlossgartenstrasse 6, 64289 Darmstadt, Germany, and Laboratoire de Chìmie des Polymeres Organiques, ENSCPB, Universite Bordeaux-1, 351 cours de la Liberation, 33405 Talence-Cedex, France
| | - Reza Ghahary
- Deutsches Kunststoff-Institut, Schlossgartenstrasse 6, 64289 Darmstadt, Germany, and Laboratoire de Chìmie des Polymeres Organiques, ENSCPB, Universite Bordeaux-1, 351 cours de la Liberation, 33405 Talence-Cedex, France
| | - Michel Schapacher
- Deutsches Kunststoff-Institut, Schlossgartenstrasse 6, 64289 Darmstadt, Germany, and Laboratoire de Chìmie des Polymeres Organiques, ENSCPB, Universite Bordeaux-1, 351 cours de la Liberation, 33405 Talence-Cedex, France
| | - Laurence Rique-Lurbet
- Deutsches Kunststoff-Institut, Schlossgartenstrasse 6, 64289 Darmstadt, Germany, and Laboratoire de Chìmie des Polymeres Organiques, ENSCPB, Universite Bordeaux-1, 351 cours de la Liberation, 33405 Talence-Cedex, France
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Evans WJ, Decoster DM, Greaves J. Evaluation of field desorption mass spectrometry for the analysis of polyethylene. J Am Soc Mass Spectrom 1996; 7:1070-1074. [PMID: 24202888 DOI: 10.1016/1044-0305(96)00043-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/1995] [Accepted: 04/22/1996] [Indexed: 06/02/2023]
Abstract
Field desorption mass spectrometry (FD-MS) has been evaluated for the analysis of low molecular weight polyethylene by using samples in the molecular weight range 600-2000 u as determined by gel permeation chromatography. The repeat units and end groups were characterized by FD-MS, but it was demonstrated that accurate molecular weight distribution data cannot be obtained for polyethylene by FD-MS because there is mass discrimination against the higher molecular weight polymers.
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Affiliation(s)
- W J Evans
- Department of Chemistry, University of California-Irvine, Irvine, California, USA
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Kühn G, Weidner S, Just U, Hohner G. Characterization of technical waxes comparison of chromatographic techniques and matrix-assisted laser-desorption/ionization mass spectrometry. J Chromatogr A 1996; 732:111-7. [DOI: 10.1016/0021-9673(95)01255-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Dienes T, Pastor SJ, Schürch S, Scott JR, Yao J, Cui S, Wilkins CL. Fourier transform mass spectrometry-advancing years (1992-mid. 1996). Mass Spectrom Rev 1996; 15:163-211. [PMID: 27082513 DOI: 10.1002/(sici)1098-2787(1996)15:3<163::aid-mas2>3.0.co;2-g] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/1996] [Revised: 10/18/1996] [Accepted: 10/22/1996] [Indexed: 06/05/2023]
Abstract
This article is one of a series of Fourier transform mass spectrometry (FTMS) reviews that has appeared in this journal at ca. 3-4 year intervals. A comprehensive review of the recent theoretical developments, instrumental developments, electrospray ionization (ESI), and MALDI is given. Ion dissociation techniques are also discussed because of their contributions to gaining insight into chemical structure. Special sections have been devoted to discussing the emerging fields of surface analysis, polymer analysis, Buckminsterfullerenes (buckyballs), and hydrogen/deuterium exchange studies. This review, although not all-inclusive, is intended to be a starting point for those wishing to learn more about the current status of FTMS, and also as a representative cross-section of the literature for those familiar with the technique. © 1997 John Wiley & Sons, Inc.
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Affiliation(s)
- T Dienes
- Department of Chemistry, University of California-Riverside, Riverside, California 92521
| | - S J Pastor
- Department of Chemistry, University of California-Riverside, Riverside, California 92521
| | - S Schürch
- Department of Chemistry, University of California-Riverside, Riverside, California 92521
| | - J R Scott
- Department of Chemistry, University of California-Riverside, Riverside, California 92521
| | - J Yao
- Department of Chemistry, University of California-Riverside, Riverside, California 92521
| | - S Cui
- Department of Chemistry, University of California-Riverside, Riverside, California 92521
| | - C L Wilkins
- Department of Chemistry, University of California-Riverside, Riverside, California 92521
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Belu AM, Desimone JM, Linton RW, Lange GW, Friedman RM. Evaluation of matrix-assisted laser desorption ionization mass spectrometry for polymer characterization. J Am Soc Mass Spectrom 1996; 7:11-24. [PMID: 24202790 DOI: 10.1016/1044-0305(95)00589-7] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/1995] [Revised: 08/07/1995] [Accepted: 08/09/1995] [Indexed: 06/02/2023]
Abstract
A protocol for the preparation of polymeric samples for time-of-flight matrix-assisted laser desorption ionization mass spectrometry (TOF-MALDI-MS) analysis was developed. Dithranol was identified as a good matrix for polystyrene (PS), and the addition of silver for cationization of molecules was determined to be necessary. Based on this preparative method, low molecular weight samples of other polymers [polyisoprene, polybutadiene, poly(ethylene oxide), poly(methyl methacrylate), and polydimethylsiloxane] were analyzed with molecular weights up to 49 ku. The effects of laser intensity were determined to influence the molecular weight distribution of intact oligomers, most significantly for low molecular weight polymers. Linear and reflectron modes of analysis were evaluated; better signal intensity and resolution were obtained in the reflectron mode. The TOF-MALDI-MS measurements are compared with time-of-flight secondary ion mass spectrometry (TOF-SIMS) and gel permeation chromatography (GPC) for the same polymers. The M n values calculated by TOF-MALDI-MS consistently are higher than values calculated by TOF-SIMS for all classes of polymers with molecular weights up to 8 ku. The molecular weights of the PS calculated from TOF-MALDI-MS are in good agreement with GPC (±10%). The composition of the terminal group on a polymer chain may affect the ion yields. The ion yields of intact oligomers were evaluated as a function of end group composition for both TOF-MALDI-MS and TOF-SIMS. The slight disparity of results between TOF-SIMS and TOF-MALDI-MS for the perfluoroalkyl-terminated PS suggests that the oligomers are desorbed preferentially from the surface in the TOF-SIMS analysis, rather than having an increased ionization probability.
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Affiliation(s)
- A M Belu
- Department of Chemistry, CB#3290, University of North Carolina, 27599-3290, Chapel Hill, NC
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Walker KL, Kahr MS, Wilkins CL, Xu Z, Moore JS. Analysis of hydrocarbon dendrimers by laser desorption time-of-flight and fourier transform mass spectrometry. J Am Soc Mass Spectrom 1994; 5:731-739. [PMID: 24222000 DOI: 10.1016/1044-0305(94)80005-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/1994] [Revised: 03/16/1994] [Accepted: 03/23/1994] [Indexed: 06/02/2023]
Abstract
The first mass spectrometric analysis of a new class of hydrocarbon dendrimers that result from a convergent synthetic approach is reported. Molecular weights of a series of phenylacetylene dendrimers (715 to 14776 u MW) are characterized by ultraviolet matrix-assisted laser desorption (MALDltime-of-flight (TOF) mass spectrometry, direct and silver chemical ionization infrared laser desorption Fourier transform mass spectrometry @I'MSl, and ultraviolet matrix-assisted laser desorption silver chemical ionization Fourier transform mass spectromeby. New matrices and techniques were developed to facilitate analysis of the dendrimers. Mass measurement accuracies between 10 and 25 ppm are obtained for molecular ion species of the five dendrimers analyzed. Laser desorption time-of-flight and FI'MS techniques are shown to be complementary, with FTMS providing high mass resolution (27,000-67,000 resolving power) and accuracy for lower mass dendrimers (10-14 ppm) and MALD TOF yielding the highest resolution (1100 resolving power) and accuracy (25 ppm) for the largest dendrimer. These results are consistent with proposed empirical formulas.
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Affiliation(s)
- K L Walker
- Department of Chemistry, University of California, Riverside, 92521, Riverside, CA
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