High-Performance Liquid Chromatography Analysis of CYP2C8-Catalyzed Paclitaxel 6α-Hydroxylation

: Paclitaxel (Taxol) is a naturally occurring member of the taxane family of antitumor drugs, which act by stabilizing microtubules. Paclitaxel is inactivated in human liver by a cytochrome P450 (P450)-catalyzed 6alpha-hydroxylation reaction. A reverse-phase, high-performance liquid chromatographic assay is described for the analysis of paclitaxel 6alpha-hydroxylation catalyzed by human liver microsomes or cDNA-expressed P450 enzyme CYP2C8. Analytical separations are achieved using a C18 column with a linear gradient of 10-100% methanol, with detection at 230 nm. This method is applicable to enzymatic studies for determination of CYP2C8-catalyzed paclitaxel 6alpha-hydroxylation activity.