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Updated: Apr 6, 2026

Efficient and Site-specific Antibody Labeling by Strain-promoted Azide-alkyne Cycloaddition
Published on: December 23, 2016
Fast and catalyst-free hydrazone ligation via ortho-halo-substituted benzaldehydes for protein C-terminal labeling at
1Department of Chemistry, University of Science and Technology of China, Hefei 230026, China. lym2007@mail.ustc.edu.cn and School of Medical Engineering, Hefei University of Technology, Hefei, Anhui 230009, China. ymli@hfut.edu.cn.
Abstract:
Rapid and catalyst-free hydrazone ligation reaction between ortho-halobenzaldehyde derivatives and peptide/protein hydrazides was observed at neutral pH and room temperature. 2-Chlorobenzaldehyde exhibited the fastest reaction and highest conversion rates among the series of ortho-halobenzaldehydes. The resulting hydrazone-containing bioconjugation products were also found to be fairly stable under experimental conditions. The new ligation strategy was successfully used for protein C-terminal labeling and should provide a practical approach for the modification of proteins.
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