Conjugation of Synthetic Oligosaccharides to Proteins by Squaric Acid Chemistry

  • Hélène B. Pfister
  • Xiaowei Lu
  • Sameh E. Soliman
  • Pavol KováčEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1954)


Oligosaccharides equipped with amine-containing linkers can be conjugated to carrier proteins using squaric acid chemistry. In a two-step process, a squarate derivative of such oligosaccharide is formed first, which is followed by its reaction with a protein carrier. Monitoring of the conjugation reaction is achieved by SELDI-TOF-MS or MALDI-TOF-MS. This experimentally simple procedure yields desired glycoconjugates in high yields and with reproducible hapten–protein ratios.

Key words

Oligosaccharides Neoglycoconjugates Squaric acid chemistry Conjugation Vaccines 


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Hélène B. Pfister
    • 1
  • Xiaowei Lu
    • 1
  • Sameh E. Soliman
    • 1
  • Pavol Kováč
    • 2
    Email author
  1. 1.National Institutes of HealthNIDDK, LBCBethesdaUSA
  2. 2.Laboratory of Bioorganic ChemistryNational Institutes of HealthBethesdaUSA

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