Chiral analysis of drug substance in clinical plasma extracts using achiral HPLC with circular dichroism detection

A circular dichroism (CD) detector in series with a W detector was used wit h reversed-phase gradient HPLC to do the chiral analysis of unresolved enan tiomers of a single stereoisomer drug substance in extracts of clinical pla sma samples. The CD/UV peak area ratio of the unresolved enantiomers in the plasma extracts was calculated and compared with pure drug substance stand ards to show that there was no racemization of the chiral center during pha rmacokinetic studies. The CD detector can be used only with chiral compound s with a UV chromophore and the limit of detection was approximately 5 ng w ith the drug substance and chromatographic conditions used in this study. ( C) 2001 Elsevier Science B.V. All rights reserved.