Used in bioconjugation and chemical synthesis, it serves as a linker molecule to connect biomolecules like proteins, peptides, or antibodies with other functional groups or surfaces. Its PEG (polyethylene glycol) spacer enhances solubility and reduces steric hindrance, making it ideal for creating stable conjugates in drug delivery systems. The carboxyl group allows for further modifications or attachment to amine-containing molecules via coupling reactions. It is also employed in the development of hydrogels, diagnostic probes, and targeted therapeutics due to its biocompatibility and versatility in cross-linking applications.