Bioconjugation

Bioconjugation designates chemical or enzymatic methodologies covalently linking biological molecules including antibodies, proteins, peptides, or nucleic acids to other molecules including drugs, labels, polymers, or nanoparticles, enabling creation of therapeutics, diagnostics, and research tools with combined functionality unavailable in individual components.

The biopharmaceutical industry employs bioconjugation extensively for antibody-drug conjugate production, PEGylation of biologics extending half-life, diagnostic antibody labelling, and targeted nanoparticle preparation. Traditional NHS ester chemistry reacts with lysine amino groups providing simple but heterogeneous conjugation. Maleimide-thiol chemistry targets engineered cysteines for more controlled conjugation. Enzymatic conjugation using sortase, transglutaminase, or formylglycine generating enzymes provides site-specificity. Bioorthogonal chemistries including click chemistry enable precise conjugation through non-natural functional groups. As next-generation conjugates require more defined structures for optimal therapeutic performance, bioconjugation chemistry continues advancing through increasingly selective, efficient, and scalable approaches.