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

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

INSTRUMENT(S): AccuTOF GC (Jeol)

SUBMITTER: Takeshi Furuhashi

PROVIDER: MTBLS215 | MetaboLights | 2015-12-27

REPOSITORIES: MetaboLights

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

Furuhashi Takeshi T Ishii Keisuke K Tanaka Kazuo K Weckwerth Wolfram W Nakamura Takemichi T

Rapid communications in mass spectrometry : RCM 20150201 3

<h4>Rationale</h4>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.<h4>Methods</h4>To evaluate the usefulness of FI in profiling isomeric saccharides by GC/MS and to explore its potential applicat ...[more]

PMID: 26411621

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			Action	DRS
	MTBLS215	Other
	FILES	Other
	a_MTBLS215_18V_EI-MS_spectra_database.txt	Txt
	a_MTBLS215_FI-MS_spectra_database.txt	Txt
	i_Investigation.txt	Txt