A rapid reversed phase high performance liquid chromatographic method for the determination of docetaxel (Taxotere) in human plasma using a column switching technique.

A rapid, simple and sensitive isocratic high performance liquid chromatography (HPLC) method was developed to measure the concentration of docetaxel in plasma samples with UV detection at 227 nm. The method uses a column switching technique with an Ultrasphere C18 column (75 x 4.6 mm ID, 3 mu, Altex, USA) as clean-up column and a CSC-nucleosil C8 column (150 x 4.6 mm ID, 5 mu, CSC, Montreal, Canada) as the analytical column. The mobile phase consisted of Phosphate buffer (30 mM, pH = 3)-acetonitrile (47:53, v/v) with the flow rates of 1.1 and 1.3 ml min-1 for clean-up and analytical columns, respectively. Paclitaxel was used as an internal standard. The plasma samples were extracted using a solid phase extraction method with Ammonium acetate (30 mM, pH = 5)-acetonitrile (50:50, v/v) as final eluent. The extraction method showed a recovery of 92% for docetaxel. In this system, the retention times of docetaxel and Paclitaxel were 7.2 and 8.5 min, respectively. The detection limit of docetaxel in plasma is 2.5 ng ml-1. This analytical method has a very good reproducibility (7.2% between-day variability at a concentration of 10 ng ml-1). It is applicable in clinical and pharmacokinetic studies.