The use of a polysaccharide-based column on multimodal elution

Amylose tris (3,5-dimethylphenylcarbamate) coated onto APS-Hypersil (5 mu m particle size and 120 Angstrom pore size) was used under normal, reversed-phase and polar-organic conditions for the enantioseparation of six racemates of different classes. The CSP was not altered when going from one mobile phase to another. All compounds were enantioresolved within the elution modes with excellent selectivity factor. The simultaneous analysis of metyrapol enantiomers and metyrapone on reversed-phase conditions and the separation of the enantiomers of omeprazole in human plasma in the polar-organic mode of elution are also described.