Comparative study on the application of capillary liquid chromatography and capillary electrochromatography for investigation of enantiomeric purity of the contraceptive drug levonorgestrel

In the last few years, it has been shown that capillary electrochromatography (CEC) is a promising technique for enantio separations. However, to date almost no studies are published on a critical comparison of CEC and its pressure-driven counterpart, capillary liquid chromatography (CLC) for real samples. In this study, the goal was to compare CLC and CEC for the determination of the enantiomeric purity of the contraceptive drug levonorgestrel and its pharmaceutical formulation. The study prevailed that not all potential advantages of CEC over CLC can easily be transformed in a real gain of detection limit of the enantiomeric impurity. However, certain advantages of CEC over CLC have been unambiguously shown. (C) 2002 Elsevier Science B.V. All rights reserved.