Used in bioconjugation processes, particularly in site-specific protein labeling. Enables efficient crosslinking of antibodies and other biomolecules for use in immunoassays, targeted drug delivery, and diagnostic imaging. Its sulfonate group enhances water solubility and stability under physiological conditions, making it suitable for applications in live-cell labeling and biotherapeutic development. Commonly employed in the preparation of antibody-drug conjugates (ADCs) where controlled conjugation is critical for maintaining biological activity and improving pharmacokinetics.