High-energy CID Mass Spectrometry of Oligosaccharides
Matrix assisted laser desorption ionization (MALDI) is a powerful and useful ionization technique that is commonly used for the analysis of biomolecules such as oligosaccharides. There are many applications of oligosaccharides in which various ionization techniques and mass spectrometers were used for their analysis . In particular, tandem mass spectrometry techniques are often used to sequence these molecules.
Recently, JEOL developed a new tandem TOF-TOF instrument coupled with MALDI that is called the Spiral- TOF. The 1st TOF consists of 4 toroidal electric sectors that fold a 17 meter flight path into a one meter box. This design provides several unique advantages for TOF-TOF analysis. The 2nd TOF has (a) 20 kV high-energy CID, (b) monoisotopic precursor ion selection, and (c) no PSD ions in the product ion mass spectrum.
In this study, we analyzed several oligosaccharides by using the JMS-S3000 SpiralTOF-TOF tandem mass spectrometer system.
All oligosaccharides (Laminaritetraose, Stachyose, α-Cyclodextrin, β-Cyclodextrin, γ-Cyclodextrin) were commercially available items that were used without further purification. Each oligosaccharide standard solution was dissolved in water. 2,5-Dihydroxybeozoic acid (DHB) was dissolved in 40% ethanol at a concentration of 10 mg/mL. Next, the oligosaccharides standard solution and matrix solution were mixed together 1:1 by volume. Afterwards, 0.5 μL of this mixture was placed on the MALDI target plate. Finally, the dried sample was measured using the JMS-S3000 SpiralTOF-TOF.