Used in bioconjugation to link biomolecules such as proteins, peptides, or antibodies in a controlled manner due to its reactive thiol ends. Commonly employed in drug delivery systems to modify therapeutic agents with PEG chains, enhancing solubility and reducing immunogenicity. Applied in surface functionalization of gold nanoparticles and other thiol-reactive surfaces for biosensors and diagnostic devices. Facilitates hydrogel formation in tissue engineering by crosslinking with maleimide or vinyl sulfone groups. Improves stability and circulation time of nanocarriers in pharmaceutical formulations.