title: Association of valdecoxib, a nonsteroidal anti-inflammatory drug, with human serum albumin.
abstract: Valdecoxib addition quenches the intrinsic human serum albumin (HSA) fluorescence. This allows an evaluation of the drug-protein association. However, both the number of binding sites and their affinity for the drug depend upon the methodology employed for their evaluation and the employed protein concentration. In this work, we measured the effect of valdecoxib on HSA fluorescence yield over a wide range of experimental conditions and discuss the validity of the binding parameters derived from the different data treatments: Stern-Volmer, Scatchard, double logarithmic, quadratic equation, Benesi-Hilderand, and Encinas-Lissi. It is proposed that a combination of Encinas-Lissi and Scatchard treatments of the data renders the most reliable results. From these data, it is concluded that HSA presents three high-affinity binding sites for valdecoxib (K(as) = 4.5 × 10(4) m(-1)) and several secondary sites of smaller activity.
authors: Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.
authors: Maria V
authors: MV
authors: Encinas
authors: Eduardo
authors: E
authors: Lissi
authors: Claudio
authors: C
authors: Vergara
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D006801:Humans; D007555:Isoxazoles / Q000494:pharmacology*; D012709:Serum Albumin / Q000187:drug effects*; D013449:Sulfonamides / Q000494:pharmacology*; D000096926:Benzenesulfonamides
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007555:Isoxazoles; D012709:Serum Albumin; D013449:Sulfonamides; C406224:valdecoxib; D000096926:Benzenesulfonamides