Used as a crosslinking agent in bioconjugation, particularly for coupling peptides or proteins to other molecules via click chemistry. Its activated ester group reacts efficiently with primary amines to form stable amide bonds, while the alkyne group allows for copper-catalyzed azide-alkyne cycloaddition (CuAAC). This dual functionality makes it valuable in drug delivery systems, diagnostic probes, and surface functionalization in biomedical research. Commonly applied in the development of antibody-drug conjugates (ADCs) and labeling biomolecules for imaging.