Hokkaido University Research Profiles

Life Sciences

MALDI Matrix for Sensitive and High-Resolution Structural Analysis of Unmodified Sialylated Glycans and Glycoconjugates

We have developed a matrix that can ionize sialylated glycans and glycoconjugates without modifying the carboxylic acid moiety of the sialic acids, and can analyze them with high sensitivity and resolution (reflector mode) without desorption of the sialic acid residue.

Content of research

Sialylation (addition of sialic acid) of glycans and glycoconjugates is an important biomarker involved in various biological phenomena such as development, differentiation, disease, infection, and immunity. MALDI (matrix-assisted laser desorption/ionization) is a simple and sensitive soft ionization method. However, the ionization efficiency of unmodified sialic acid-containing glycans is low, and there is a problem that the spectrum becomes complicated due to cleavage of sialic acids or other reasons. With this technique, we succeeded in measuring sialylated glycans and glycoconjugates with high sensitivity and high resolution without undergoing any modification process by improving the addition system to the conventional matrix while suppressing sialic acid desorption. With the change in the cleavage pattern and the increased sensitivity, TOF/TOF analysis and pseudo-MS3 analysis can now be performed using ultra-trace samples. This method does not require chemical modification and separation steps, and enables reaction tracking and rapid sample analysis.

  • Analysis results using a conventional matrix
    (Lower sensitivity and more complex peaks)

  • Results of analysis of the same sample at the same concentration using a new matrix (more than 100 times higher sensitivity has been achieved)

  • TOF/TOF analysis using this matrix shows that not only sialic acid but also reducing terminal sugar residues are preferentially cleaved.

  • Pseudo MS/MS/MS analysis enables detailed sequence analysis of glycopeptide glycans.

Potential for social implementation

  • The application of this technology is expected to accelerate the quality control of sialylated glycans and glycoconjugates and related biomarker discovery research.

Appealing points to industry and local governments

This is a new technology published in 2019. We intend to accelerate our research and strengthen our patent by filing a priority application.

Intellectual property related to this research

特願2019-011457 「未修飾シアリル化複合糖質および糖ペプチドのリフレクトロンモードMALDI-TOFおよびTOF/TOF質量分析のためのアニリン誘導体/DHB/アルカリ金属 マトリックス」