Collisional Activation Dissociation Mass Spectrometry Studies of Oligosaccharides Conjugated with Na⁺-Encapsulated Dibenzo-18-Crown-6 Ether

Abstract

: To determine the influence of the cationization agent on the collision activated dissociation (CAD) fragmentation behavior of oligosaccharides, the CAD spectra of the singly protonated, sodiated oligosaccharides and singly sodiated and dibenzo-18-crown-6 ether conjugated oligosaccharides were carefully compared. Each of these three different species showed quite different fragmentation spectra. The comparison of singly protonated and sodiated oligosaccharide CAD spectra revealed that different cationization agents affected the cationization agent adduction sites as well as the fragmentation sites within the oligosaccharides. When the mobility of Na + was limited by the dibenzo-18-crown-6 ether encapsulation agent, the examined linear oligosaccharides showed fragmentation patterns quite different from the unmodified ones. For the dibenzo-18-crown-6 ether conjugated oligosaccharides, the charge-remote fragmentation pathways were more likely to be activated than the chargedirected pathways. This work demonstrates that dibenzo-18-crown-6 ether conjugation can potentially provide a route to selectively activate the charge-remote fragmentation pathways, albeit to a limited extent, in tandem mass spectrometry studies.

Analysis of Carbohydrates and Glycoconjugates by Matrix‐assisted Laser Desorption/Ionization Mass Spectrometry: An Update for 2015–2016

“…Linear oligosaccharides adducted with sodium fragment mainly by charge‐directed fragmentation. However, when the mobility of sodium is limited by encapsulation into dibenzo‐18‐crown‐6 ( 47 ), charge‐remote fragmentation pathways have been found to dominate the fragmentation spectra (Bae et al, 2016). These pathways were mainly B and C glycosidic cleavages and X‐type cross‐ring reactions.…”