The phenomenon responsible for enantioseparation in chromatographic and electrophoretic methods is the same; it is the enantioselective interaction between the enantiomers and a chiral selector. The principal difference between these two techniques arises from different separation process mechanisms and sometimes different environments of complexation The remarkable capacity of cyclodextrin (CD) for enantioseparation has been used to advantage in many chromatographic and electrophoretic applications The chromatographic and electrophoretic methods which are very sensitive to structure, size, shape and dynamics of the analytes have been used not only in separation science but also in the study of molecular recognition proceses. The enantiomeric separation of basic chiral pharmaceuticals such as pheniramine, brompheniramine, metoxyphenamine, cyclopentolate, doxylamine, and ketamine was investigated in capillary electrophoresis (CE) and liquid chromatography (HPLC) using negatively charged sulfated-?-cyclodextrin (s-?-CD) and neutral cyclodextrins (CDs). The apparent stability constants for the model compounds with cyclodextrins in both techniques were estimated. Both methods seem to be complementary for the study of complexation phenomena. It can be seen that brompheniramine forms stronger complexes with ?-CD than pheniramine and doxylamine. Complexation of pheniramine and doxylamine by ?-CD is very similar. The weakest complexes ?-CD forms with metoxyphenamine. For the studied compounds, TM-?-CD forms very weak complexes. The stability constant for DM-?-CD is very similar to that obtained for ?-CD. From the native CDs the best chiral selectors for the studied compounds are ?-CD and HP-?-CD. For the studied compounds the best recognition between enantiomers was obtained for cyclopentolate (K1/K2=1.32, K1/K2 =1.45 and K1/K2 =1.26 for ?-CD,for HP-?-CD and TM-?-CD, respectively) As the CE is the more efficient method, chiral recognition is better visible in this method than in HPLC. Conclusions: The obtained results shows that chromatographic and electrophoretic methods may be used as additional tools for studying weak interactions responsible for molecular recognition between ligand and receptor.

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