Unusual Fragmentation Patterns of Lignin Model Compounds with α-O-4 Linkages in (+) ESI/Tandem Mass Spectrometry

摘要

This study showed that positive ion-mode ESI with sodium or lithium attachment is an effective way to ionize lignin model compounds with α-O-4 as well as β-O-4 linkages without fragmentation, which could not be done by using traditional negative ion-mode ESI. CAD of the lithiated molecule with an α-O-4 linkage results in loss of a lignin monomer, which is useful for sequencing. Sodiated molecules provide less structural information. The lithiated molecule with only β-O-4 linkages showed exclusively losses of small neutral molecules (H_2O and CH_2O). Further experiments on CAD of other model compounds with α-O-4 linkages are underway.