Widely used in bioconjugation and drug delivery systems, this compound serves as a linker molecule due to its PEG (polyethylene glycol) spacer, which enhances solubility and reduces immunogenicity. The maleimide group allows for selective conjugation with thiol-containing molecules, such as cysteine residues in proteins or peptides, enabling precise attachment of therapeutic agents or targeting moieties. Its hydrophilic PEG chain improves the stability and circulation time of conjugated drugs, making it valuable in developing antibody-drug conjugates (ADCs) and other targeted therapies. Additionally, it is utilized in surface modification of nanoparticles to improve their biocompatibility and targeting efficiency in biomedical applications.