ENANTIOSELECTIVE SEPARATION OF CHIRAL ARYLCARBOXYLIC ACIDS ON AN IMMOBILIZED HUMAN SERUM-ALBUMIN CHIRAL STATIONARY-PHASE

A series of 12 chiral arylcarboxylic acids were chromatographed on an immobilized human serum albumin chiral stationary phase (HSA-CSP). The effects of solute structure on chromatographic retentions and enantio selective separations were examined by linear regression analysis and the construction of quantitative structure-enantioselective retention relationships. Competitive displacement studies were also conducted us ing R-ibuprofen as the displacing agent. The results indicate that the enantioselective retention of the solutes takes place at the indole-b enzodiazepine site (site II) on the HSA molecule and that chiral recog nition is affected by the hydrophobicity and steric volume of the solu tes. The displacement studies also identified a cooperative allosteric interaction induced by the binding of R-ibuprofen to site II. (C) 199 7 Wiley-Liss, Inc.