Propargyl-PEG6-NH2 is widely used in bioconjugation and chemical biology for labeling and modifying biomolecules. Its propargyl group enables click chemistry reactions, particularly copper-catalyzed azide-alkyne cycloaddition (CuAAC), making it valuable for attaching fluorescent dyes, drugs, or other functional groups to peptides, proteins, or nucleic acids. The PEG6 spacer enhances solubility and reduces steric hindrance, improving the efficiency of reactions. Additionally, the amine group allows for further functionalization or conjugation to carboxyl groups via standard coupling reactions. This compound is particularly useful in drug delivery systems, diagnostic imaging, and the development of bioconjugates for targeted therapies.