2-Iminothiolane hydrochloride is widely used in biochemical research for modifying proteins and peptides. Its primary application is in the introduction of thiol groups into molecules, facilitating the formation of disulfide bonds or conjugation with other thiol-reactive compounds. This property makes it valuable in the study of protein structure and function, as well as in the development of bioconjugates for therapeutic and diagnostic purposes. Additionally, it is employed in the preparation of affinity chromatography resins, where thiol groups are essential for coupling ligands to solid supports. Its ability to enhance the reactivity of biomolecules under mild conditions makes it a versatile tool in various biotechnological applications.