This compound is primarily utilized in bioconjugation and chemical biology due to its azide functional group, which enables click chemistry reactions, particularly copper-catalyzed azide-alkyne cycloaddition (CuAAC). The PEG9 spacer enhances solubility and reduces steric hindrance, making it suitable for linking biomolecules or modifying surfaces. It is often employed in drug delivery systems, protein labeling, and the development of biomaterials. Additionally, the thioester group allows for selective reactivity with thiol-containing molecules, facilitating site-specific modifications in peptides or proteins. Its applications extend to creating functionalized nanoparticles, hydrogels, and other advanced materials for biomedical research.