Used as a key reagent in chemical biology and proteomics research, particularly in sulfur fluoride exchange (SuFEx) click chemistry. It acts as an electrophilic labeling agent that selectively reacts with nucleophilic amino acid residues such as lysine and tyrosine in proteins, enabling covalent modification for target identification and mapping protein interactions. Its high reactivity and stability make it valuable for developing activity-based protein profiling (ABPP) probes. Also employed in the synthesis of covalent inhibitors and functionalized biomolecules for drug discovery. Due to its ability to form stable sulfonate linkages, it is utilized in materials science for constructing robust polymer networks and functional surfaces.