STUDIES ON THE BINDING OF NALIDIXIC-ACID TO SERUM ALBUMINS USING SITEMARKERS IBUPROFEN AND PHENYLBUTAZONE

Through the binding with nalidixic acid, bovine serum albumin (BSA) an d human serum albumin (HSA) could quench the characteristic fluorescen ce of nalidixic acid-terbium chelate. Because of the tight binding of phenylbutazone and ibuprofen to the special sites of albumins, they we re used as the binding site markers on the albumins. In this paper the different effects of BSA and HSA on the fluorescence of nalidixic aci d-terbium chelate were discussed. According to the displacement of the site markers on albumins, the binding site of nalidixic acid on the B SA has been found to be the I special binding site.