Separation and identification of cetirizine enantiomers in human urine by CE and circular dichroism independent of their standards.

Enantioseparation and determination of chiral drugs are of vital importance in biochemical and pharmaceutical research, due to the different biological activity, mechanism, and toxicity of individual enantiomers. As a second-generation H(1)-antagonist, cetirizine's pharmaceutical activity is mainly derived from the levocetirizine while the dextro-enantiomer is ineffective and even associated with side effects. Herein, the enantiomers of cetirizine were separated by CE and identified by electronic circular dichroism. Satisfactory linear relationship was found between the circular dichroism signal at λ max and the electrophoretic peak area difference in the nonracemic mixture of enantiomers. It made possible identification and quantification of cetirizine enantiomers independent of single enantiomer standards. The method's feasibility was demonstrated on the enantiomeric excess experiments of oral drugs measured in human blank urine. Additionally, the separation and determination of cetirizine in human urine after administration were also realized by CE, indicating the method was sensitive enough for pharmacokinetic study. This article is protected by copyright. All rights reserved.