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Updated: May 29, 2026

Efficient and Site-specific Antibody Labeling by Strain-promoted Azide-alkyne Cycloaddition
Published on: December 23, 2016
Reliable and efficient procedures for the conjugation of biomolecules through Huisgen azide-alkyne cycloadditions
Enrique Lallana1, Ricardo Riguera, Eduardo Fernandez-Megia
1Department of Organic Chemistry and Center for Research in Biological Chemistry and Molecular Materials (CIQUS), University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Abstract:
The Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) has been established as a powerful coupling technology for the conjugation of proteins, nucleic acids, and polysaccharides. Nevertheless, several shortcomings related to the presence of Cu, mainly oxidative degradation by reactive oxygen species and sample contamination by Cu, have been pointed out. This Minireview discusses key aspects found in the development of the efficient and benign functionalization of biomacromolecules through CuAAC, as well as the Cu-free strain-promoted azide-alkyne cycloaddition (SPAAC).
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