Used as a crosslinking agent in bioconjugation, it facilitates the attachment of proteins, peptides, or antibodies to other molecules or surfaces. Its NHS ester group reacts with primary amines, forming stable amide bonds, while the SPDP group allows for thiol-reactive conjugation. This makes it valuable in drug delivery systems, where it helps create targeted therapeutic agents by linking drugs to carriers like antibodies or nanoparticles. It is also employed in diagnostic assays to label biomolecules for detection and imaging purposes. The PEG12 spacer enhances solubility and reduces steric hindrance, improving the efficiency of conjugation reactions in various biomedical applications.