Electrokinetic separation of enantiomers using a capillary coated with poly-terguride

Enantioseparation of 2-arylpropionic acids (Flobufen) and dansyl-derivatives of amino acids can be achieved in 10-15 min by electrochromatography using a capillary coated with poly-terguride. It was found that the analytes, in the range of the buffer pH between 2.5-4.0, were driven by anodic electroosmotic flow originated by the positively charged moieties of the ergolinic skeleton, and, only partially, by their anodic electrophoretic mobility. The enantiomers eluted with the same sequence, e.g. L- or (S)-isomer more retained than D- or (R)-, which was observed in HPLC separations on terguride-silica based CSPs, thus indicating that racemates were resolved by a similar chiral recognition mechanism. The retention of the solutes was affected by the concentration and composition of the effluent. An other mobile phase variable, strongly affecting the selectivity, was the pH of the buffer.