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Fouquet T, Torimura M, Sato H. Multi-stage Mass Spectrometry of Poly(vinyl pyrrolidone) and Its Vinyl Succinimide Copolymer Formed upon Exposure to Sodium Hypochlorite. ACTA ACUST UNITED AC 2016; 5:A0050. [PMID: 27800293 DOI: 10.5702/massspectrometry.a0050] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 09/26/2016] [Indexed: 11/23/2022]
Abstract
The degradation routes of poly(vinyl pyrrolidone) (PVP) exposed to sodium hypochlorite (bleach) have been previously investigated using chemical analyses such as infrared spectroscopy. So far, no reports have proposed mass spectrometry (MS) as an alternative tool despite its capability to provide molecular and structural information using its single stage electrospray (ESI) or matrix assisted laser desorption ionization (MALDI) and multi stage (MS n ) configurations, respectively. The present study thus reports on the characterization of PVP after its exposure to bleach by high resolution MALDI spiralTOF-MS and Kendrick mass defect analysis providing clues as to the formation of a vinyl pyrrolidone/vinyl succinimide copolymeric degradation product. A thorough investigation of the fragmentation pathways of PVP adducted with sodium and proton allows one main route to be described-namely the release of the pyrrolidone pendant group in a charge remote and charge driven mechanism, respectively. Extrapolating this fragmentation pathway, the oxidation of vinyl pyrrolidone into vinyl succinimide hypothesized from the single stage MS is validated by the detection of an alternative succinimide neutral loss in lieu of the pyrrolidone release in the ESI-MS n spectra of the aged PVP sample. It constitutes an example of application of multi-stage mass spectrometry for the characterization of the degradation of polymeric samples at a molecular level.
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Affiliation(s)
- Thierry Fouquet
- National Institute of Advanced Industrial Science and Technology (AIST)
| | - Masaki Torimura
- National Institute of Advanced Industrial Science and Technology (AIST)
| | - Hiroaki Sato
- National Institute of Advanced Industrial Science and Technology (AIST)
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2
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Polymer architectures via mass spectrometry and hyphenated techniques: A review. Anal Chim Acta 2016; 932:1-21. [DOI: 10.1016/j.aca.2016.05.024] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 04/07/2016] [Accepted: 05/16/2016] [Indexed: 11/22/2022]
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Fouquet T, Sato H. Convenient visualization of high-resolution tandem mass spectra of synthetic polymer ions using Kendrick mass defect analysis - the case of polysiloxanes. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:1361-1364. [PMID: 27173118 DOI: 10.1002/rcm.7560] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 03/11/2016] [Accepted: 03/11/2016] [Indexed: 06/05/2023]
Affiliation(s)
- Thierry Fouquet
- National Institute of Advanced Industrial Science and Technology (AIST), Environmental Measurement Technology Group, Environmental Management Research Institute (EMRI), 16-1 Onogawa, Tsukuba, Ibaraki, 305-8569, Japan
| | - Hiroaki Sato
- National Institute of Advanced Industrial Science and Technology (AIST), Environmental Measurement Technology Group, Environmental Management Research Institute (EMRI), 16-1 Onogawa, Tsukuba, Ibaraki, 305-8569, Japan
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Antoine R, Lemoine J, Dugourd P. Electron photodetachment dissociation for structural characterization of synthetic and bio-polymer anions. MASS SPECTROMETRY REVIEWS 2014; 33:501-22. [PMID: 24285407 DOI: 10.1002/mas.21402] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 12/21/2012] [Accepted: 01/08/2013] [Indexed: 05/25/2023]
Abstract
Tandem mass spectrometry (MS-MS) is a generic term evoking techniques dedicated to structural analysis, detection or quantification of molecules based on dissociation of a precursor ion into fragments. Searching for the most informative fragmentation patterns has led to the development of a vast array of activation modes that offer complementary ion reactivity and dissociation pathways. Collisional activation of ions using atoms, molecules or surface resulting in unimolecular dissociation of activated ions still plays a key role in tandem mass spectrometry. The discovery of electron capture dissociation (ECD) and then the development of other electron-ion or ion/ion reaction methods, constituted a significant breakthrough, especially for structural analysis of large biomolecules. Similarly, photon activation opened promising new frontiers in ion fragmentation owing to the ability of tightly controlled internal energy deposition and easy implementation on commercial instruments. Ion activation by photons includes slow heating methods such as infrared multiple photon dissociation (IRMPD) and black-body infrared radiative dissociation (BIRD) and higher energy methods like ultra-violet photodissociation (UVPD) and electron photo detachment dissociation (EPD). EPD occurs after UV irradiation of multiply negatively charged ions resulting in the formation of oxidized radical anions. The present paper reviews the hypothesis regarding the mechanisms of electron photo-detachment, radical formation and direct or activated dissociation pathways that support the observation of odd and even electron product ions. Finally, the value of EPD as a complementary structural analysis tool is illustrated through selected examples of synthetic polymers, oligonucleotides, polypeptides, lipids, and polysaccharides.
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Affiliation(s)
- Rodolphe Antoine
- University of Lyon, F-69622, Lyon, France; CNRS et Université Lyon 1, UMR5306, Institut Lumière Matière, Villeurbanne, France
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Lee J, Lee S, Yoon D, Yoon WJ, Im SS, Moon B, Oh HB. Tandem mass spectrometric analysis of isosorbide-1,4-cyclohexane-dicarboxylic acid polyester oligomer cations using ion-trap mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2013; 27:1913-1918. [PMID: 23939957 DOI: 10.1002/rcm.6645] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 05/25/2013] [Accepted: 06/02/2013] [Indexed: 06/02/2023]
Abstract
RATIONALE Isosorbide is a promising biomass-derived molecule that can be used as a replacement for fossil resource-derived diol monomers used in polyester synthesis. Due to its increased use in sustainable development, it is useful to understand the tandem mass spectrometric (MS/MS) fragmentation pathways of the isosorbide-based copolymer as an aid to interpreting the MS/MS spectra of other isosorbide-containing copolymers. METHODS Collision-activated dissociation (CAD) experiments were performed on the sodiated/protonated molecules, [(AB)(n)A+Na(or H)](+), n = 2-5, of isosorbide (A)-1,4-cyclohexanedicarboxylic acid (B) oligomers formed by ion-trap electrospray ionization (ESI). RESULTS Product ions arose from cleavage of the bonds between isosorbide and 1,4-cyclohexanedicarboxylic acid. In the MS/MS spectra, f(n)'' product ions were most abundant, followed by e(n) ions. McLafferty rearrangement appeared to provide the most facile pathway to yield the abundant f(n)'' and e(n) ions. In addition, a(n), b(n)'', f(n)''u(n)'', and en (+) ions were observed. Inductive cleavage and β-elimination were suggested to be the pathways involved in generating e(n)(+)- and e(n)/b(n)''-type ions, respectively. CONCLUSIONS Based on the obtained CAD spectra, the alternating sequences of two copolymer building blocks, A and B, were unambiguously determined. The fragmentation pathways leading to the observed product ion types were also established.
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Affiliation(s)
- Jihye Lee
- Department of Chemistry, Sogang University, Seoul 121-742, Korea
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Soeriyadi AH, R.Whittaker M, Boyer C, Davis TP. Soft ionization mass spectroscopy: Insights into the polymerization mechanism. ACTA ACUST UNITED AC 2013. [DOI: 10.1002/pola.26536] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Girod M, Brunet C, Antoine R, Lemoine J, Dugourd P, Charles L. Efficient structural characterization of poly(methacrylic acid) by activated-electron photodetachment dissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:7-11. [PMID: 22048905 DOI: 10.1007/s13361-011-0279-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 10/04/2011] [Accepted: 10/12/2011] [Indexed: 05/31/2023]
Abstract
Characterization of end-groups in poly(methacrylic acid) (PMAA) was achieved using tandem mass spectrometry after activated-electron photodetachment dissociation (activated-EPD). In this technique, multiply deprotonated PMAA oligomers produced in the negative-ion mode of electrospray ionization were oxidized into radical anions upon electron photodetachment using a 220 nm laser wavelength, and further activated by collision. In contrast to conventional collision induced dissociation of negatively charged PMAA, which mainly consists of multiple dehydration steps, fragmentation of odd-electron species is shown to proceed via a radical-induced decarboxylation, followed by reactions involving backbone bond cleavages, giving rise to product ions containing one or the other oligomer termination. A single radical-induced mechanism accounts for the four main fragment series observed in MS/MS. The relative position of the radical and of the anionic center in distonic precursor ions determines the nature of the reaction products. Experiments performed using PMAA sodium salts allowed us to account for relative abundances of product ions in series obtained from PMAA, revealing that ion stability is ensured by hydrogen bonds within pairs of MAA units.
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Affiliation(s)
- Marion Girod
- Université de Lyon, 69622 Villeurbanne cedex, France
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Girod M, Antoine R, Lemoine J, Dugourd P, Charles L. End-group characterization of poly(styrene sulfonate sodium salt) by activated electron photo-detachment dissociation. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:3259-3266. [PMID: 22006388 DOI: 10.1002/rcm.5228] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Tandem mass spectrometry of poly(styrene sulfonate sodium salt) (PSS) was performed after activated electron photo-detachment dissociation (activated EPD). In this technique, doubly charged PSS oligomers were first produced in negative mode electrospray ionization, then oxidized into radical anions upon electron photo-detachment using a 220 nm laser wavelength, and further activated by collision. In contrast to the collision-induced dissociation (CID) of negatively charged PSS oligomers, which does not provide informative data with regard to the end-groups, activated-EPD is shown here to promote radical-induced dissociation reactions thanks to the oxidation of a sulfonate group upon laser irradiation. Major product ions generated after backbone bond cleavages contained one or the other chain terminations and could be accounted for by two main mechanisms. Moreover, each of the proposed dissociation reactions was shown to generate two distinct fragments, depending on the location of the oxidized monomer near one or the other chain terminal moieties. As a result, a combination of these two fragments allowed a straightforward mass characterization of each end-group.
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Affiliation(s)
- Marion Girod
- Université de Lyon, F-69622 Villeurbanne cedex, France
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Wesdemiotis C, Solak N, Polce MJ, Dabney DE, Chaicharoen K, Katzenmeyer BC. Fragmentation pathways of polymer ions. MASS SPECTROMETRY REVIEWS 2011; 30:523-559. [PMID: 20623599 DOI: 10.1002/mas.20282] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Revised: 11/05/2009] [Accepted: 11/05/2009] [Indexed: 05/29/2023]
Abstract
Tandem mass spectrometry (MS/MS) is increasingly applied to synthetic polymers to characterize chain-end or in-chain substituents, distinguish isobaric and isomeric species, and determine macromolecular connectivities and architectures. For confident structural assignments, the fragmentation mechanisms of polymer ions must be understood, as they provide guidelines on how to deduce the desired information from the fragments observed in MS/MS spectra. This article reviews the fragmentation pathways of synthetic polymer ions that have been energized to decompose via collisionally activated dissociation (CAD), the most widely used activation method in polymer analysis. The compounds discussed encompass polystyrenes, poly(2-vinyl pyridine), polyacrylates, poly(vinyl acetate), aliphatic polyester copolymers, polyethers, and poly(dimethylsiloxane). For a number of these polymers, several substitution patterns and architectures are considered, and questions regarding the ionization agent and internal energy of the dissociating precursor ions are also addressed. Competing and consecutive dissociations are evaluated in terms of the structural insight they provide about the macromolecular structure. The fragmentation pathways of the diverse array of polymer ions examined fall into three categories, viz. (1) charge-directed fragmentations, (2) charge-remote rearrangements, and (3) charge-remote fragmentations via radical intermediates. Charge-remote processes predominate. Depending on the ionizing agent and the functional groups in the polymer, the incipient fragments arising by pathways (1)-(3) may form ion-molecule complexes that survive long enough to permit inter-fragment hydrogen atom, proton, or hydride transfers.
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Affiliation(s)
- Chrys Wesdemiotis
- Department of Chemistry, The University of Akron, OH 44325-3601, USA.
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Fouquet T, Humbel S, Charles L. Tandem mass spectrometry of trimethylsilyl-terminated poly(dimethylsiloxane) ammonium adducts generated by electrospray ionization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2011; 22:649-658. [PMID: 21472604 DOI: 10.1007/s13361-010-0073-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 12/23/2010] [Accepted: 12/27/2010] [Indexed: 05/30/2023]
Abstract
Ammonium adducts of trimethylsilyl-terminated poly(dimethylsiloxane) (CH(3)-PDMS) produced by electrospray ionization were submitted to collision induced dissociation and revealed a particular MS/MS behavior: the same three main product ions at m/z 221, 295, and 369 were always generated in very similar relative abundances regardless of the size of the precursor ion. Combining accurate mass measurements and ab initio calculation allowed very stable cyclic geometries to be obtained for these ionic species. Dissociation mechanisms were proposed to account for the three targeted ions to be readily generated in a two-step or a three-step reaction from any CH(3)-PDMS ammonium adducts. A second set of three product ions was also observed with low abundance at m/z 207, 281, and 355, which were shown in MS(3) experiments to be formed in secondary reactions. An alternative dissociation process was shown to consist of a concerted elimination of ammonia and methane and the need for a methyl of an end-group to be involved in the released methane molecule would account for this reaction to mainly proceed from the smallest precursor ions.
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Affiliation(s)
- Thierry Fouquet
- Universités Aix-Marseille I, II & III-CNRS, UMR 6264, Laboratoire Chimie Provence, Spectrométries Appliquées à la Chimie Structurale, Campus Saint-Jérôme, Marseille, France
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Giordanengo R, Viel S, Hidalgo M, Allard-Breton B, Thévand A, Charles L. Methylation of acidic moieties in poly(methyl methacrylate-co-methacrylic acid) copolymers for end-group characterization by tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2010; 24:1941-1947. [PMID: 20552705 DOI: 10.1002/rcm.4591] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The complete structural characterization of a copolymer composed of methacrylic acid (MAA) and methyl methacrylate (MMA) units was achieved using tandem mass spectrometry. In a first step, collision-induced dissociation (CID) of sodiated MAA-MMA co-oligomers allowed us to determine the co-monomeric composition, the random nature of the copolymer and the sum of the end-group masses. However, dissociation reactions of MAA-based molecules mainly involve the acidic pendant groups, precluding individual characterization of the end groups. Therefore, methylation of all the acrylic acid moieties was performed to transform the MAA-MMA copolymer into a PMMA homopolymer, for which CID mainly proceeds via backbone cleavages. Using trimethylsilyldiazomethane as a derivatization agent, this methylation reaction was shown to be complete without affecting the end groups. Using fragmentation rules established for PMMA polymers together with accurate mass measurements of the product ions and knowledge of reagents used for the studied copolymer synthesis, a structure could be proposed for both end groups and it was found to be consistent with signals obtained in nuclear magnetic resonance spectra.
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Affiliation(s)
- Rémi Giordanengo
- Universités Aix-Marseille I, II et III-CNRS, UMR 6264: Laboratoire Chimie Provence, Spectrométries Appliquées à la Chimie Structurale, F-13397 Marseille, France
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Giordanengo R, Viel S, Hidalgo M, Allard-Breton B, Thévand A, Charles L. Analytical strategy for the molecular weight determination of random copolymers of poly(methyl methacrylate) and poly(methacrylic acid). JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:1075-1085. [PMID: 20202862 DOI: 10.1016/j.jasms.2010.02.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Revised: 02/01/2010] [Accepted: 02/06/2010] [Indexed: 05/28/2023]
Abstract
Molecular weight characterization of random amphiphilic copolymers currently represents an analytical challenge. In particular, molecules composed of methacrylic acid (MAA) and methyl methacrylate (MMA) as the repeat units raise issues in commonly used techniques. The present study shows that when random copolymers cannot be properly ionized by MALDI, and hence detected and measured in MS, one possible analytical strategy is to transform them into homopolymers, which are more amenable to this ionization technique. Then, by combining the molecular weight of the so-obtained homopolymers, as measured by MS, with the relative molar proportion of the MMA and MMA units, as given by (1)H NMR spectrum, one can straightforwardly estimate the molecular weight of the initial copolymer. A methylation reaction was performed to transform MAA-MMA copolymer samples into PMMA homopolymers, using trimethylsilyldiazomethane as a derivatization agent. Weight average molecular weight (M(w)) parameters of the MAA-MMA copolymers could then be derived from M(w) values obtained for the methylated MAA-MMA molecules by MALDI, which were also validated by pulsed gradient spin echo (PGSE) NMR. An alkene function in one of the studied copolymer end-groups was also shown to react with the methylation agent, giving rise to MMA-like polymeric by-products characterized by tandem mass spectrometry and which could be avoided by adjusting the amount of the trimethylsilyldiazomethane in the reaction medium.
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Affiliation(s)
- Rémi Giordanengo
- Universités Aix-Marseille I, II, and III-CNRS, UMR 6264: Laboratoire Chimie Provence, Spectrométries Appliquées à la Chimie Structurale, Marseille, France
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Affiliation(s)
- Steffen M. Weidner
- Federal Institute for Materials Research and Testing (BAM), D-12489 Berlin, Richard-Willstaetter-Strasse 11, Germany, and Department of Chemistry, Wayne State University, 5101 Cass Avenue, 33 Chemistry, Detroit, Michigan 48202
| | - Sarah Trimpin
- Federal Institute for Materials Research and Testing (BAM), D-12489 Berlin, Richard-Willstaetter-Strasse 11, Germany, and Department of Chemistry, Wayne State University, 5101 Cass Avenue, 33 Chemistry, Detroit, Michigan 48202
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Gruendling T, Weidner S, Falkenhagen J, Barner-Kowollik C. Mass spectrometry in polymer chemistry: a state-of-the-art up-date. Polym Chem 2010. [DOI: 10.1039/b9py00347a] [Citation(s) in RCA: 194] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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The incorporation of metal cations into polymer backbones: An important consideration in the interpretation of ESI-MS spectra. POLYMER 2009. [DOI: 10.1016/j.polymer.2009.09.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Crecelius AC, Baumgaertel A, Schubert US. Tandem mass spectrometry of synthetic polymers. JOURNAL OF MASS SPECTROMETRY : JMS 2009; 44:1277-1286. [PMID: 19676098 DOI: 10.1002/jms.1623] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The detailed characterization of macromolecules plays an important role for synthetic chemists to define and specify the structure and properties of the successfully synthesized polymers. The search for new characterization techniques for polymers is essential for the continuation of the development of improved synthesis methods. The application of tandem mass spectrometry for the detailed characterization of synthetic polymers using the soft ionization techniques matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and electrospray ionization mass spectrometry (ESI-MS), which became the basic tools in proteomics, has greatly been increased in recent years and is summarized in this perspective. Examples of a variety of homopolymers, such as poly(methyl methacrylate), poly(ethylene glycol), as well as copolymers, e.g. copolyesters, are given. The advanced mass spectrometric techniques described in this review will presumably become one of the basic tools in polymer chemistry in the near future.
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Affiliation(s)
- Anna C Crecelius
- Laboratory of Organic and Macromolecular Chemistry, Friedrich-Schiller-University Jena, Humboldtstrasse 10, 07743 Jena, Germany
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Giordanengo R, Viel S, Hidalgo M, Allard-Breton B, Thévand A, Charles L. Structural characterization of a poly(methacrylic acid)-poly(methyl methacrylate) copolymer by nuclear magnetic resonance and mass spectrometry. Anal Chim Acta 2009; 654:49-58. [PMID: 19850168 DOI: 10.1016/j.aca.2009.06.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 06/16/2009] [Accepted: 06/18/2009] [Indexed: 12/01/2022]
Abstract
Mass spectrometry (MS) and nuclear magnetic resonance (NMR) have been combined to achieve the complete microstructural characterization of a poly(methacrylic acid)-poly(methyl methacrylate) (PMAA-PMMA) copolymer synthesized by nitroxide-mediated polymerization. Various PMAA-PMMA species could be identified which mainly differ in terms of terminaisons. 1H and 13C NMR experiments revealed the structure of the end-groups as well as the proportion of each co-monomer in the copolymers. These end-group masses were further confirmed from m/z values of doubly charged copolymer anions detected in the single stage mass spectrum. In contrast, copolymer composition derived from MS data was not consistent with NMR results, obviously due to strong mass bias well known to occur during electrospray ionization of these polymeric species. Tandem mass spectrometry could reveal the random nature of the copolymer based on typical dissociation reactions, i.e., water elimination occurred from any two contiguous MAA units while MAA-MMA pairs gave rise to the loss of a methanol molecule. Polymer backbone cleavages were also observed to occur and gave low abundance fragment ions which allowed the structure of the initiating end-group to be confirmed.
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Affiliation(s)
- Rémi Giordanengo
- Universités Aix-Marseille I, II et III-CNRS, UMR 6264: Laboratoire Chimie Provence, Spectrométries Appliquées à la Chimie Structurale, F-13397 Marseille, France
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