Optimization of Electrospray Ionization (ESI)

Due to the acidity and lability of sulfate groups present on GAGs, ESI is the preferred technique because it can result in little or no in-source fragmentation when properly tuned (1). Optimization of the ESI tuning parameters is crucial for the accurate MS analysis of sulfated GAGs.

• Extent and position of sulfation can lead to varying degrees of lability for every oligosaccharide. The lability of the sulfate groups increases as the size of the heparin oligosaccharide increases.
• Successful ESI tuning parameters are more easily achieved using highly sulfated hexasaccharide standards with defined structures (NEB# P0738, P0739) as compared to smaller disaccharide standards

1. Kim, Y. S et al. (1998) Glycobiology 8(9):869-877. PMID: 9675219