Used in bioconjugation and click chemistry applications, it serves as a linker molecule for attaching biomolecules or functional groups. Its propargyl group enables efficient copper-catalyzed azide-alkyne cycloaddition (CuAAC), making it valuable for labeling proteins, peptides, or other biomolecules. The PEG3 spacer enhances solubility and reduces steric hindrance, improving reaction efficiency. It is particularly useful in drug delivery systems, diagnostic assays, and the development of targeted therapies.