Used primarily in the field of bioconjugation and drug delivery, this compound serves as a versatile linker molecule. It is commonly employed to modify peptides, proteins, and other biomolecules, enhancing their solubility, stability, and bioavailability. The t-butyl ester group provides protection for the carboxyl group, allowing selective deprotection during synthesis. Its PEG (polyethylene glycol) spacer improves water solubility and reduces immunogenicity, making it valuable in the development of therapeutic agents, particularly in targeted cancer therapies and antibody-drug conjugates. Additionally, it is utilized in the preparation of functionalized materials for biomedical research and diagnostics.