The binding of flurbiprofen to plasma proteins.

The binding of flurbiprofen to human serum albumin and normal plasma was measured using ultracentrifugation. Flurbiprofen was bound in excess of 99% in all cases. Over the concentration range normally associated with therapy the data could be adequately described by a one-site binding model. The association constant decreased with increasing protein concentration, being 3.04 X 10(6) M-1 at an albumin concentration, of 2 g/100 ml and 1.19 X 10(6) M-1 at a concentration of 4 g/100 ml. Flurbiprofen binding showed no dependence on pH over the range 7.0 to 8.0.