Tandem mass spectrometry of synthetic polymers

Crecelius, Anna C.; Baumgaertel, Anja; Schubert, Ulrich S.

doi:10.1002/jms.1623

Cited by 78 publications

(72 citation statements)

References 62 publications

(115 reference statements)

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“…Inherent viscosity (η inh ) values were low, especially for PIA-III derived from the diacid III obtained with L-phenylalanine. MALDI-TOF mass spectrometry was used as an essential tool for the characterization of synthetic polymers and determines the absolute molecular weight distributions (24)(25)(26). In the analysis of the PIAs, it was possible to observe m/z signals which were assigned to protonated and sodium forms associated to average molecular mass ranging from 1180 to 3219 m/z ( Table 2).…”

Section: Polymer Synthesismentioning

confidence: 99%

Synthesis of Oligomeric Silicon-containing Poly(imide-amide)s Derived from Trimellitic Anhydride and Amino-Acids. Vibration Spectral, Optical, Thermal and Morphological Characterization

Tagle

Terraza

Ortiz

et al. 2012

Journal of Macromolecular Science, Part A

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Poly(imide-amide)s (PIAs) were synthesized from diacids, which were obtained by trimellitic anhydride and glycine, L-alanine, Lphenylalanine, L-valine, L-leucine, L-isoleucine and p-aminobenzoic acid, and bis(4-aminophenyl)diphenylsilane. Compounds were characterized by elemental analysis, optical activity, IR and NMR spectroscopies. Yields were good, but η inh values were low, showing materials of oligomeric nature, confirmed by MALDI-TOF spectrometry. PIAs were soluble in polar aprotic solvents, while those derived from amino acids with bulky side groups were soluble in CHCl 3 and acetone. The wavenumber of vibrational bands were compared by Infrared and Raman spectroscopy. However, the high fluorescence emitted for PIAs, difficult to predict the vibrations of certain functional groups by Raman spectroscopy. The incorporation of chiral, amide and imide moieties interrupt the conjugation and increase the flexibility of the system. In addition, the adjacent phenyl units from the silicon-containing diamine, disfavors the planar conformation, which affects the optical properties showing an insulator behavior. DSC analyses showed that PIA-VII of aromatic nature had the higher glass transition temperature (Tg) value. For the other PIAs the Tg values decreased when volume of the side groups was increased, with the exception of PIA-VI derived from L-isoleucine. The thermal decomposition temperatures showed that only PIA-VII derived from p-aminobenzoic acid was thermostable. For the other PIAs it was possible to see a decrease of the TDT values when the size of the side chain is increased. The size and shape of the polymeric particles were studied by Scanning Electronic Microscopy (SEM), showing a relation between structure, incorporation of rigid aromatic rings and voluminous group into the system.

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Section: Polymer Synthesismentioning

confidence: 99%

Synthesis of Oligomeric Silicon-containing Poly(imide-amide)s Derived from Trimellitic Anhydride and Amino-Acids. Vibration Spectral, Optical, Thermal and Morphological Characterization

Tagle

Terraza

Ortiz

et al. 2012

Journal of Macromolecular Science, Part A

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“…Matrix-assisted laser desorption/ionization (MALDI) has become an important analytical technique in the study of a range of compounds, 1 including peptides 2,3 and synthetic polymers, 4,5 from which accurate end-group analysis and molecular weight determination, including both whole mass and sequence information, can be obtained. [6][7][8][9][10][11] Recently, Spengler et al 12 reported that fragment analysis of a variety of compounds generated by the MALDI process can allow linkage information to be obtained by post-source delay (PSD), whereas others have extended this to in-source decay (ISD), 13 electron-capture dissociation, 14 or terminal sequencing 15 , thereby furthering the utility of the MALDI technique.…”

Section: Introductionmentioning

confidence: 99%

The use of a silica-based heat sink to “uncouple” the matrix-assisted laser desorption/ionization (MALDI) mechanism

et al. 2011

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The relationships between ion yield(s) as a function of desorption alone and (or) ionization was investigated using two model systems. In the first model system, a carbohydrate (2,3,6-tri-O-methyl-b-cyclodextrin, TMBCD), which could be directly laser desorbed, was analyzed with and without a silicon-based heat sink compound (HSC). The HSC allowed heat to pass through but obstructed the flow of charge. In the second model system, a peptide (substance P), which ccould not be laser desorbed, was analyzed under similar conditions. The ion yield of TMBCD under either system of heat conductivity was similar, whereas the ion yield of the peptide with the heat sink was negligible. Compounds that are predominately cationized either in the gas phase or preformed in solution give an ion yield that is not dependent upon the surface conditions, whereas compounds that are not ordinarily cationized are affected by the emission of electrons from the metal surface.Résumé : Faisant appel à deux systèmes modèles, on a étudié les relations entre les rendements ioniques en fonction de la désorption seule et (ou) de l'ionisation. Dans le premier système modèle, on a analysé un hydrate de carbone, la 2,3,6-tri-O-méthyl-b-cyclodextrine, TMBCD, qui peut être désorbée avec et sans composé dissipateur thermique (CDT) à base de silicone. Le CDT permet la libre circulation de la chaleur, mais obstrue les déplacements de la charge. Dans le deuxième système modèle, on a analysé dans les mêmes conditions un peptide (substance P) qui ne peut pas être désorbé par le laser. Le rendement ionique en TMBCD est semblable quel que soit le système de conductivité thermique alors que le rendement ionique du peptide avec le dissipateur thermique est négligeable. Les composés qui sont d'une façon prédominante cationisés en phase gazeuse ou préformés en solution donnent un rendement ionique qui ne dépend pas des conditions superficielles alors que les composés qui ne sont habituellement pas cationisés sont affectés par l'émission d'électrons par la surface métallique.Mots-clés : dissipateur thermique, désorption laser assistée par la matrice (DLAM), désorption/ionisation assistée par la matrice (DILAM), émission d'électron.[Traduit par la Rédaction]

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“…therewith by far the analytical possibilities in polymer chemistry. [3][4][5] Since then, a large variety of synthetic polymers has been investigated by MALDI-MS methods, such as polystyrene (PS) and poly(methyl methacrylate) (PMMA). Also poly(ethylene glycol) (PEG) is very well investigated by MALDI-MS techniques as it provides an easily ionizable structure.…”

Section: Introductionmentioning

confidence: 99%

Systematic MALDI‐TOF CID Investigation on Different Substituted mPEG 2000

Knop

Jahn

Hager

et al. 2010

Macro Chemistry & Physics

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Methoxy poly(ethylene glycol) 2000 (mPEG 2000) samples were substituted via esterification reactions to convert the hydroxyl end group of the mPEG into potential initiators for the cationic ring opening polymerization of 2‐oxazolines. These substitution products were investigated by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS); in addition, detailed MALDI‐TOF/TOF‐collision induced dissociation (CID) MS studies were performed to introduce this method as complementary structural characterization tool allowing the detailed analysis of the prepared macromolecules. The CID of the macroinitiators revealed 1,4‐hydrogen and 1,4‐ethylene eliminations forming very regular fragmentation patterns which showed, depending on the end groups, different fragmentation series. Furthermore, very pronounced McLafferty + 1 rearrangements (1,5 hydrogen‐transfer) of the introduced ester end groups were observed leaving the mPEG molecule as neutral acid. This incisive loss revealed the exact molar mass for each end group and, therefore, represents an important tool for end group determination of functionalized polymers.magnified image

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Tandem mass spectrometry of synthetic polymers

Cited by 78 publications

References 62 publications

Synthesis of Oligomeric Silicon-containing Poly(imide-amide)s Derived from Trimellitic Anhydride and Amino-Acids. Vibration Spectral, Optical, Thermal and Morphological Characterization

Synthesis of Oligomeric Silicon-containing Poly(imide-amide)s Derived from Trimellitic Anhydride and Amino-Acids. Vibration Spectral, Optical, Thermal and Morphological Characterization

The use of a silica-based heat sink to “uncouple” the matrix-assisted laser desorption/ionization (MALDI) mechanism

Systematic MALDI‐TOF CID Investigation on Different Substituted mPEG 2000

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