A quartz crystal resonant sensor (QCRS) study of HSA-drug interactions

Human serum albumin (HSA) was immobilised on the gold surface of a quartz c rystal resonance sensor (QCRS) and exposed to warfarin and diazepam, Distin ct decreases in frequency of differing magnitudes were observed upon exposu re of the protein to each of the compounds suggesting strongly that a ligan d interaction was occurring. Moreover, as sequential exposure in any order was observed to yield distinct repeatable frequency decreases for the ligan ds indicated, screening for site specific binding may be possible, Identica lly immobilised bovine serum albumin (BSA) gave no response to either compo und.