Unusual effects of separation conditions on chiral separations

Unusual effects in Liquid chromatographic separations of enantiomers on chi ral stationary phases are reviewed with emphasis on polysaccharide phases. On protein phases and Pirkle phases reversal of the elution order between e nantiomers due to variation of temperature and mobile phase composition has been reported. Most of the nonanticipated observations have dealt with the widely used polysaccharide phases. Reversed retention order and other ster eoselective effects have been observed by variation of temperature, organic modifier and water content in nonpolar organic mobile phases. (C) 2001 Els evier Science B.V, All rights reserved.