Fragmentation patterns of methyloxime-trimethylsilyl derivatives of constitutive mono- and disaccharide isomers analyzed by gas chromatography/field ionization mass spectrometry

Author(s)
Takeshi Furuhashi, Keisuke Ishii, Kazuo Tanaka, Wolfram Weckwerth, Takemichi Nakamura
Abstract

RATIONALE In saccharide analysis by gas chromatography/mass spectrometry (GC/MS), electron ionization (EI) is used almost exclusively, whereas other gentler methods of ionization are rarely used. Field ionization (FI) is recognized as a GC/MS ionization method that causes fewer fragment ions, but only few studies are available on its use in saccharide analysis.

METHODS To evaluate the usefulness of FI in profiling isomeric saccharides by GC/MS and to explore its potential application in metabolome analysis, we compared EI, chemical ionization (CI), and FI spectral patterns of consecutive mono- and disaccharides derivatized with methoxamine-HCl and N-methyl-N-(trimethylsilyl)trifluoroacetamide.

RESULTS FI produced molecular ions and fragment ions characteristic of constitutive isomeric disaccharides. All of the derivatized saccharides that originally had free anomeric OH showed methyloxime-moiety fragment ions, attributable to the cleavage between C2 and C3. Some fragment ions in FI were indicative of the position of dihexose linkages. Although EI with lowered voltage (18 V, 130 °C) produced fewer fragment ions than conventional EI (70 V, 250 °C) did, fragmentation patterns were different from those of FI.

CONCLUSIONS Our data show that FI is useful for distinguishing isomeric saccharides in qualitative analyses.

Organisation(s)
External organisation(s)
Ulmer Fundamental Symmetries Laboratory, JEOL Ltd., Japan
Journal
Rapid Communications in Mass Spectrometry
Volume
29
Pages
238-246
No. of pages
9
ISSN
0951-4198
DOI
https://doi.org/10.1002/rcm.7105
Publication date
02-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
106002 Biochemistry, 104002 Analytical chemistry, 104026 Spectroscopy
Keywords
ASJC Scopus subject areas
Spectroscopy, Analytical Chemistry, Organic Chemistry
Portal url
https://ucrisportal.univie.ac.at/en/publications/9826709e-c125-4e98-8e2f-6c9b92deb01c