Fragmentation study of a 8-C-glycosyl isoflavone, puerarin, using electrospray ion trap time-of-flight mass spectrometry at high resolution.

A mass spectrometry method that combines electrospray with an ion trap time-of-flight mass analyzer has been used to characterize puerarin (7,4'-dihydroxyisoflavone-8-C-beta-D-glucoside). MS(n) spectra (n <or= 6) were obtained in positive and negative ion mode. The combination of accurate mass measurement in MS(2) spectra and sequential MS(n) experiments enabled fragmentation pathways to be elucidated in detail. A novel structure for [M+H-150]+ has been found. Copyright (c) 2007 John Wiley & Sons, Ltd.