title: Effect of temperature on binding of warfarin by human serum albumin.
abstract: The in vitro binding of warfarin by human serum albumin was studied at various temperatures and at pH 7.4 by a frontal gel filtration technique. The results can be best described in terms of a two class-of-binding site model, in which the numbers of primary and secondary sites are constrained to the average values for all experiments (n1 = 1.38 and n2 = 3.73). Analysis of the temperature dependence of the binding yielded the following thermodynamic parameters: deltaH1 =-2.55 kcal/mole, deltaS1=16.1 eu, and deltaF1=-7.34 kcal/mole for the primary binding and deltaH2=-5.08 kcal/mole, deltaS2=-1.10 eu, and deltaF2=4.72 kcal/mole for the secondary binding. Calculations based on these results showed that, for the therapeutic concentration range, warfarin was over 99% bound to albumin present in physiological concentration. These findings are compared and contrasted to binding data in the literature for warfarin and salicylate.
mesh_terms: D001665:Binding Sites; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008954:Models, Biological; D011485:Protein Binding; D012459:Salicylates / Q000097:blood; D012709:Serum Albumin / Q000378:metabolism*; D013696:Temperature; D013816:Thermodynamics; D014859:Warfarin / Q000097:blood*
chemical_list: D012459:Salicylates; D012709:Serum Albumin; D014859:Warfarin