Used as a bifunctional linker in bioconjugation and surface modification due to its thiol and hydroxyl groups. The thiol group readily binds to gold surfaces, making it useful in the formation of self-assembled monolayers (SAMs) for sensors and biosensors. The primary alcohol allows further chemical derivatization, enabling attachment of biomolecules or polymers. Commonly employed in nanotechnology, particularly in functionalizing gold nanoparticles for drug delivery, diagnostics, and molecular recognition. Also used in the synthesis of thiol-terminated polyethylene glycol (PEG) derivatives and as a building block in organic synthesis where selective reactivity is required.