Widely used in bioconjugation and drug delivery systems due to its cleavable disulfide linker and hydrophilic PEG spacers. The disulfide bond (SS) is sensitive to reducing environments, such as those found inside cells, enabling controlled release of payloads like drugs or imaging agents. The dual PEG6 chains enhance water solubility, reduce immunogenicity, and improve the pharmacokinetic profile of conjugated molecules. Commonly employed in the development of antibody-drug conjugates (ADCs), targeted therapies, and nanoparticle functionalization. Its terminal acid groups allow straightforward coupling to amines or hydroxyls via standard conjugation chemistry, making it a versatile linker in pharmaceutical research and bioconjugate engineering.