A flow platform for degradation-free CuAAC bioconjugation

Area of Science:

• Bioconjugation Chemistry
• Flow Chemistry
• Catalysis

Background:

• Copper-catalyzed azide-alkyne cycloaddition (CuAAC) is vital for biomolecule ligation.
• Concerns regarding copper-mediated oxidation and contamination limit CuAAC's biomedical applications.

Purpose of the Study:

• To develop a generic CuAAC flow platform for rapid and robust bioconjugate formation.
• To address limitations of traditional batch CuAAC reactions, specifically copper contamination and oxidation.

Main Methods:

• Utilized solvent-mediated copper pipe erosion under laminar flow to generate catalytic copper in situ.
• Applied the flow platform to various substrates including small molecules, fluorophores, drugs, peptides, DNA, and oligonucleotides.

Main Results:

• Achieved efficient CuAAC reactions at ambient temperature and pressure with short residence times.
• Demonstrated formation of discrete triazole bioconjugates with significantly reduced copper contamination (ppm levels).
• Avoided oxidation of sensitive functional groups present in biomolecules and drug conjugates.

Conclusions:

• The developed flow platform offers a superior alternative to batch CuAAC for bioconjugation.
• This method enhances the biomedical utility of CuAAC by ensuring high purity and integrity of bioconjugates.