This chemical is primarily used in the field of bioconjugation and drug delivery systems. Its structure, featuring a tert-butyl ester and a polyethyleneglycol (PEG) chain, makes it highly suitable for modifying proteins, peptides, and other biomolecules. The PEG segment enhances solubility, reduces immunogenicity, and extends the circulation time of conjugated drugs in the body. The tert-butyl group serves as a protective moiety that can be selectively removed under mild conditions, allowing for controlled release or activation of the active compound. It is particularly valuable in the development of targeted therapies, such as antibody-drug conjugates (ADCs), where precise delivery of therapeutic agents to specific cells or tissues is critical. Additionally, its application extends to the formulation of hydrogels and other biocompatible materials used in tissue engineering and regenerative medicine.