Used in bioconjugation for the preparation of antibody-drug conjugates (ADCs), enabling controlled linkage of cytotoxic agents to monoclonal antibodies. Its pyridyldithio group facilitates reversible disulfide bond formation, allowing for stable yet cleavable connections in targeted drug delivery systems. Commonly employed in the development of therapeutic biologics where precise coupling and controlled release are critical. Also utilized in immobilizing biomolecules onto surfaces for diagnostic assays and biosensors due to its selective reactivity with thiol groups.