A Study of Alkali Halide Triple Ions by Fast Atom Bombardment and Collisionally Activated Dissociation Mass Spectrometry.

Substituted benzoic and cinnamic acids were studied by FAB mass spectrometry using matrix-based Al(III) ions. Complex ions derived from these acids, such as ( M + 117 )+ ( 117 = (Al + glycerol − 2H)+ ), ( M + 159 )+ ( 159 = [2Al + 2glycerol − 5H − 74(epoxypropanol)]+), and ( M + 233)+ ( 233 = (2Al + 2glycerol − 5H)+), when subjected to collisionally activated dissociation (CAD), gave an ion corresponding to ( M − OH)+. Formation of this ion was explained by the transfer of the carboxylic -OH group to the ( Al + glycerol − 2H)+, ( 2Al + 2glycerol − 5H − 74 )+, and ( 2Al + 2glycerol − 5H )+ portion of the complexes. This transfer is more pronounced in the case of meta- and para-substituted acids. The CAD of the ( M + 117 )+ ions yielded ( M + Al(III) )+ ions resulting from the insertion of Al(III) into the carboxylic acid, which was followed by the elimination of CO to produce ( M + Al(III) − CO)+ ions. Interpretation of spectral data was clarified by study of the formation and fragmentation of ions produced from deuterated benzoic and cinnamic acids. Keywords: substituted benzoic and trans-cinnamic acids, Al(III)–glycerol, FAB mass spectrometry, ionic metal complexes, collisionally induced dissociation, Al(III) insertion, carbonyl cations.

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Determination of sequence and linkage of tissue oligosaccharides in caprine ?-mannosidosis by fast atom bombardment, collisionally activated dissociation tandem mass spectrometry

Glycoconjugate Journal ◽

10.1007/bf00780759 ◽

1992 ◽

Vol 9 (3) ◽

pp. 126-131 ◽

Cited By ~ 8

Author(s):

Douglas A. Gage ◽

Eileen Rathke ◽

Catherine E. Costello ◽

Margaret Z. Jones

Keyword(s):

Mass Spectrometry ◽

Tandem Mass Spectrometry ◽

Fast Atom Bombardment ◽

Tandem Mass ◽

Collisionally Activated Dissociation

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Characterization of the ethyl-triphenylphosphonium derivative of model peptides by fast atom bombardment collisionally-activated dissociation tandem mass spectrometry using B/E linked scans

International Journal of Mass Spectrometry and Ion Processes ◽

10.1016/0168-1176(91)85055-q ◽

1991 ◽

Vol 111 ◽

pp. 191-209 ◽

Cited By ~ 27

Author(s):

J. Throck Watson ◽

David S. Wagner ◽

Yoon-Seok Chang ◽

John R. Strahler ◽

Samir M. Hanash ◽

...

Keyword(s):

Mass Spectrometry ◽

Tandem Mass Spectrometry ◽

Fast Atom Bombardment ◽

Tandem Mass ◽

Collisionally Activated Dissociation ◽

Model Peptides

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Effects of Doping on the Electrochemical and Electrical Properties of Poly(2,5-di(2-thienyl)pyrrole)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19991357 ◽

1999 ◽

Vol 64 (8) ◽

pp. 1357-1368 ◽

Cited By ~ 7

Author(s):

Enric Brillas ◽

José Carrasco ◽

Ramon Oliver ◽

Francesc Estrany ◽

Víctor Ruiz

Keyword(s):

Mass Spectrometry ◽

Fast Atom Bombardment ◽

Oxidation Potential ◽

Ethanolic Solution ◽

Pt Electrode ◽

Reversible Process ◽

Oxidation Potentials ◽

Lower Productivity ◽

Polymeric Chains ◽

Linear Molecules

The electropolymerization of 2,5-di(2-(thienyl)pyrrole) (SNS) on a Pt electrode from ethanolic solution with LiClO4 or LiCl as electrolyte has been studied by cyclic voltammetry (CV) and chronoamperometry (CA). In both media, a quasi-reversible process has been indicated by CV, reversing the scan at low oxidation potentials. Under these conditions, reducible positive charges formed in both oxidized polymers are compensated by the entrance of anions from solution. Elemental analysis reveals that polymers generated at a low oxidation potential by CA contain a 21.03% (w/w) of ClO4- or a 9.56% (w/w) of Cl-. The poly(SNS) doped with Cl- presents higher proportion of reducible positive charges, higher polymerization charge and lower productivity. A much higher electrical conductivity, however, has been found for the poly(SNS) doped with ClO4-. Both polymers are soluble in DMSO, acetone and methanol. The dimer, trimer, tetramer and pentamer have been detected as soluble and neutral linear oligomers by mass spectrometry-fast atom bombardment. The analysis of polymers by infrared spectroscopy confirms the predominant formation of linear molecules with α-α linkages between monomeric units. A condensation mechanism involving one-electron oxidation of all electrogenerated linear and neutral polymeric chains is proposed to explain the SNS electropolymerization.

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