Stereospecific high-performance liquid chromatographic assay of isosakuranetin in rat urine

A stereospecific method of analysis of racemic isosakuranetin (5,7-dihydroxy-4'-methoxyflavanone) in biological fluids is necessary to study pharmacokinetics. A simple high-performance liquid chromatographic method was developed for the determination of isosakuranetin enantiomers. Separation was achieved on a Chiralpak (R) AD (TM)-RH column with ultraviolet (UV)-detection at 286 nm. The standard curves in urine were linear ranging from 0.5 to 100.0 mu g/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 mu g/ml). Bias of the assay was < 15% and was within 6% at the limit of quantitation. The assay was applied successfully to stereospecific disposition of isosakuranetin enantiomers in rat urine. (c) 2008 Elsevier B.V. All rights reserved.