Related Experiment Videos
Derivatization for stabilizing sialic acids in MALDI-MS
Sadanori Sekiya1, Yoshinao Wada, Koichi Tanaka
1Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, Nakagyo-ku, Kyoto 604-8511, Japan. sekiya@shimadzu.co.jp
Analytical Chemistry
|August 2, 2005
Summary
Amidation stabilizes sialic acid in oligosaccharides during MALDI-MS analysis. This derivatization method enhances structural analysis by preventing dissociation and improving ion yield for N-acetylneuraminic acid-containing glycans.
Area of Science:
- Analytical Chemistry
- Glycobiology
- Mass Spectrometry
Background:
- Sialic acids, like N-acetylneuraminic acid (NANA), are crucial in biological processes but prone to dissociation during MALDI-MS.
- This instability complicates the analysis of sialylated oligosaccharides.
Purpose of the Study:
- To develop a derivatization method to stabilize the NANA moiety in oligosaccharides for improved MALDI-MS analysis.
- To evaluate the effectiveness of amidation in preventing NANA dissociation and enhancing structural information.
Main Methods:
- Amidation of the NANA moiety using 4-(4,6-dimethoxy-1,3,5-triazin-2yl)-4-methylmorpholinium chloride as a condensing agent.
- Analysis of derivatized and underivatized sialylated oligosaccharides using MALDI-MS and MS/MS.
Main Results:
- Amidation effectively stabilized the glycosidic bond of NANA, suppressing dissociation during in-source, postsource, and collision-induced decay.
- The method significantly improved the yield of B/Y ions, facilitating MS/MS-based structural elucidation.
- Using (15)N-labeled ammonium chloride for amidation minimized mass shifts, simplifying spectral interpretation and database searching.
Conclusions:
- Amidation is a robust derivatization strategy to enhance the structural analysis of sialylated oligosaccharides by MALDI-MS.
- This approach overcomes the challenge of NANA lability, providing more reliable and detailed glycan structural information.