This heterobifunctional crosslinker, featuring N-hydroxysuccinimide (NHS) ester and maleimide reactive groups connected by a long polyethylene glycol (PEG) chain, is primarily used in bioconjugation applications. It enables site-specific covalent linking of biomolecules, such as proteins, antibodies, and peptides, by reacting NHS esters with primary amines (e.g., lysine residues) and maleimides with thiols (e.g., cysteine residues). This makes it ideal for creating antibody-drug conjugates, surface modifications in biosensors, and targeted drug delivery systems. Its water-soluble PEG spacer enhances solubility and reduces immunogenicity in biological environments. Additionally, it is employed in the synthesis of hydrogels and polymeric scaffolds for tissue engineering, wound healing, and cell encapsulation in biomedical research.