Differentiation of flavonoid glycoside isomers by using metal complexation and electrospray ionization mass spectrometry

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Abstract

The elucidation of flavonoid isomers is accomplished by electrospray ionization tandem mass spectrometry (ESI-MS/MS) via formation and collisional activated dissociation (CAD) of metal/flavonoid complexes containing an auxiliary ligand. Addition of a metal salt and a suitable neutral auxiliary ligand to flavonoids in solution results in the formation of [M(II) (flavonoid-H) ligand]+ complexes by ESI which, upon collisional activated dissociation, often result in more distinctive fragmentation patterns than observed for conventional protonated or deprotonated flavonoids. Previously, 2,2′-bipyridine was used as an auxiliary ligand, and now we compare and explore the use of alternative pyridyl ligands, including 4,7-diphenyl-1,10-phenanthroline. Using this technique, three groups of flavonoid glycoside isomers are differentiated, including glycosides of apigenin, quercetin, and luteolin.

Keywords

Flavonoid Bipyridine Collisional Activate Dissociation Flavonoid Glycoside Quercitrin 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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© American Society for Mass Spectrometry 2003

Authors and Affiliations

  1. 1.Department of Chemistry and BiochemistryThe University of Texas at AustinAustinUSA

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