title: Consequences of the N-B transition of albumin for the binding of warfarin in human serum.
abstract: The protein binding of warfarin in serum has been studied by means of circular dichroism and equilibrium dialysis. Evidence was found that the N-B transition of albumin, occurring around physiological pH, takes place not only in solutions of pure albumin but also in serum. The protein binding of warfarin in serum is pH-dependent and increases with pH especially around physiological pH. This pH-dependent serum binding of warfarin can be reasonably explained by the N-B transition of albumin. The effect of Ca2+ and Mg2+ on the protein binding of warfarin in serum is negligible at pH 7.4, whereas at this pH Cl- increases the free-warfarin concentration by a competitive displacement.
mesh_terms: D002118:Calcium / Q000494:pharmacology; D002712:Chlorides / Q000494:pharmacology; D003956:Dialysis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D011487:Protein Conformation / Q000187:drug effects; D012709:Serum Albumin / Q000378:metabolism*; D014859:Warfarin / Q000097:blood*
chemical_list: D002712:Chlorides; D012709:Serum Albumin; D014859:Warfarin; D008274:Magnesium; D002118:Calcium