Enantiomeric separations and their application in pharmaceutical analysis using chiral eluents

The most important problems of enantiomeric separations using chiral eluents are discussed. The methods have been compared with respect to enantiomeric purity of reagents, reagent selection and separation variables. The most important considerations for methods based on inclusion-complexation with different CDs and on using chiral counter ions are summarised and compared. A new possibility for the separation of enantiomeric compounds with the aid of a combination of ion-pair and inclusion-complex formation has been introduced. As a consequence of this investigation, the selectivity of the separation can be significantly improved; those ionic isomers and enantiomers which cannot be separated or are unsatisfactorily separated by ion-pair chromatography or by inclusion-complex formation, can be separated by the combined technique. Comparison of methods applicable for enantiomeric separations is also given with respect to solving specific analytical tasks in the field of pharmaceutical analysis.