Isosakuranetin (ISK)

Isosakuranetin is a flavanone, a type of flavonoid. It can be found in the fruit of Citrus sinensis (blood orange), in the fruit of Citrus x paradisi (grapefruit) and in Monarda didyma (scarlet beebalm). 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 AD-RH column with ultraviolet (UV)-detection at 286 nm. The standard curves in urine were linear ranging from 0.5 to 100.0 microg/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 microg/ml). Bias of the assay was <15% and was within 6% at the limit of quantitation.