Stereospecific high‐performance liquid chromatography of taxifolin, applications in pharmacokinetics, and determination in tu fu ling ( Rhizoma smilacis glabrae ) and apple ( Malus × domestica )

A stereospecific method of analysis of racemic taxifolin (+/−3,5,7,3′,4′‐pentahydroxyflavanone) in biological fluids is necessary to study pharmacokinetics and disposition in fruit and herbs. A simple high‐performance liquid chromatographic method was developed for the determination of all four taxifolin enantiomers. Separation was achieved on a Chiralcel® OJ‐RH column with UV detection at 288 nm. The standard curves in serum were linear over a range of 0.5–100.0 µg/mL for each enantiomer. The mean extraction efficiency was >88.0%. Precision of the assay was <15% (CV), and was within 12% at the limit of quantitation (0.5 µg/mL). The bias of the assay was <15%, and was within 6% at the limit of quantitation. The assay was successfully applied to stereospecific disposition of taxifolin enantiomers in rats and to the quantification of taxifolin enantiomers in tu fu ling ( Rhizoma smilacis glabrae ) and apple ( Malus × domestica ). Copyright © 2009 John Wiley & Sons, Ltd.