This chemical is widely used in bioconjugation and click chemistry applications. It serves as a linker or spacer molecule in the development of drug delivery systems, enabling the attachment of therapeutic agents to targeting molecules like antibodies or peptides. Its PEG4 chain enhances solubility and reduces immunogenicity, making it suitable for biomedical research. Additionally, it is utilized in the synthesis of proteolysis-targeting chimeras (PROTACs) for targeted protein degradation. Its propargyl group allows for efficient copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions, a key technique in bioorthogonal chemistry. This compound is also employed in the preparation of functionalized nanoparticles and biomaterials for diagnostic and therapeutic purposes.