Used extensively in bioconjugation and chemical biology, it serves as a linker molecule for attaching functional groups to biomolecules like proteins, peptides, and antibodies. Its PEG4 spacer enhances solubility and reduces steric hindrance, making it ideal for creating stable conjugates in drug delivery systems. It is also employed in the synthesis of antibody-drug conjugates (ADCs) and targeted therapies, where precise attachment of therapeutic agents is crucial. Additionally, it finds use in surface modification of nanoparticles and materials for biomedical applications, improving biocompatibility and targeting efficiency.