Used as a bifunctional crosslinker in bioconjugation to link biomolecules such as proteins, peptides, or drugs through carboxyl group reactions. Enables the formation of hydrogels for tissue engineering by crosslinking with amines or alcohols. Improves solubility and stability of drug conjugates in pharmaceutical formulations. Applied in surface modification of nanoparticles and medical devices to enhance biocompatibility and reduce nonspecific protein adsorption. Commonly used in controlled release systems due to its tunable hydrophilic spacer length.