NMR Spectroscopic Diffusion, Chemical Shift and Linewidth Measurements of Low-Affinity Binding of Ibuprofen Enantiomers to Human Serum Albumin

摘要

The binding of racemic, (R)(-) and (S)(+)-ibuprofen (IBP) to human serum albumin (HSA) was studied using NMR spectroscopy. Having saturated the tight binding sites, the extent of weak binding was then investigated. The molecular diffusion coefficients of IBP in HSA solution at different concentration ratios indicate that there is no significant difference in binding capacity of the two enantiomers of IBP to HSA at high IBP: HSA ratios. However, there are chemical shift and linewidth changes in the ~1NMR spectrum of IBP in the presence of HSA induced by the binding and this suggests that the major binding interaction involves the sec-butyl chain of the IBP molecule binding to HSA in hydrophobic pockets.