Disuccinimidyl Sulfoxide

Disuccinimidyl Sulfoxide (CAS No.: 1351828-03-9) is a sulfoxide-containing, amine-reactive homobifunctional crosslinker widely employed in chemical crosslinking and mass spectrometry–based proteomics to investigate protein structure and interactions. This reagent selectively targets primary amino groups, such as those found on lysine residues and protein N-termini, forming covalent linkages that stabilize protein–protein interactions and higher-order assemblies. A defining feature of this crosslinker is the presence of two symmetric collision-induced dissociation–cleavable sites, which enable predictable fragmentation during tandem mass spectrometry analysis, thereby facilitating the confident identification and mapping of crosslinked peptides within complex biological samples. Functionally, it operates as a structural probe rather than a modulator of specific signaling pathways, providing spatial and interactional information critical for elucidating protein complex architecture and conformational dynamics. In vitro applications commonly include studies of purified proteins, model peptides, and multisubunit complexes, as well as cell lysates, where it supports interactome profiling and structural biology workflows. Experimental concentrations typically fall within the low micromolar to millimolar range depending on sample composition and analytical objectives. As a research tool, Disuccinimidyl Sulfoxide is integral to advancing mechanistic understanding in systems biology and drug discovery, particularly in efforts aimed at characterizing protein networks and validating molecular interactions.