m-nitrobenzyl alcohol electrochemistry in fast atom bombardment mass spectrometry

AbstractRapid identification of solanesol even in the presence of a complex matrix can be accomplished using fast atom bombardment (FAB) mass spectrometry in combination with tandem mass spectrometry methods. FAB MS analysis using a nitrobenzyl alcohol matrix doped with lithium yields an abundant (M + Li)+ ion of m/z of 637 which is a very characteristic marker for the presence of solanesol and is quite sufficient for screening for the presence of solanesol in many cases. MS/MS analysis of this ion produces a spectrum which yields specific structural information regarding each isoprene unit of the entire structure. Furthermore, these methods are very useful for characterizing unknowns as demonstrated by the characterization of diol, triol and ester impurities in commercially available solanesol. Application of the MS/MS/MS analysis provides insight into the fragmentation mechanism and can be a useful alternative to conventional labeling methods for confirming spectral interpretations.

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The use ofm-nitrobenzyl alcohol as a matrix in fast atom bombardment mass spectrometry

Rapid Communications in Mass Spectrometry ◽

10.1002/rcm.1290020107 ◽

1988 ◽

Vol 2 (1) ◽

pp. 18-21 ◽

Cited By ~ 39

Author(s):

M. Barber ◽

D. Bell ◽

M. Eckersley ◽

M. Morris ◽

L. Tetler ◽

...

Keyword(s):

Mass Spectrometry ◽

Fast Atom Bombardment ◽

Nitrobenzyl Alcohol

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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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