The energetics of the interaction of piroxicam with plasma albumin

Abstract

The thermodynamics of the binding of piroxicam to human and bovine plasma albumins revealed the reactions to be spontaneous and exothermic with bond strengths indicating the involvement of hydrogen and hydrophobic bonds. The association constants (K) decreased as temperature increased for both human serum albumin (HSA) and bovine serum albumin (BSA); and at all the temperatures in this study, K values obtained for BSA were higher (except at 36 degrees C) but not the bound fraction of piroxicam (beta) and the quantity of binding (V). Scatchard plots of the data indicated at least two classes of binding sites.