Immobilized Polysaccharide-Based Stationary Phases for Enantioseparation in Normal Versus Reversed Phase HPLC

A set of 31 structurally different chiral pharmaceutical compounds was used as model analytes for investigation of the enantioselective potential of two immobilized polysaccharide-based chiral stationary phases under normal and reversed phase separation conditions. These chiral stationary phases differed in the polymeric backbone, amylose or cellulose, but possessed the same derivatization functionality. The results showed that the tris(3,5-dimethylphenylcarbamate) of amylose and cellulose have very broad, and often complementary, enantiorecognition abilities. In general, normal phase separation mode seemed to be more advantageous for separation of the majority of studied pharmaceuticals no matter if amylose- or cellulose-based columns were used. However, in certain cases the reversed phase separation system yielded better results. The combination of these two immobilized chiral stationary phases offers a powerful tool for enantioseparation of different types of pharmaceuticals in the normal and/or reversed phase mode.