Used as an irreversible serine protease inhibitor in biochemical and biomedical research. It effectively inactivates enzymes such as trypsin, chymotrypsin, and plasmin by covalently modifying active site serine residues. Commonly applied in cell lysis buffers to prevent protein degradation during extraction and purification processes. Also utilized in proteomics studies to profile enzyme activity and identify active site-containing proteins. Its ability to cross cell membranes makes it suitable for both in vitro and in vivo applications where inhibition of intracellular proteases is required. Often included in cocktail inhibitors to maintain sample integrity in western blotting, ELISA, and other protein detection techniques.