Serum containing docetaxel was combined with acetonitrile containing deuterated internal standard, and following protein precipitation, supernatant was diluted with water for on-line sample extraction. Following turbulent-flow chromatography (TFC), analytic separation was achieved on a Hypersil Gold C-18 (50 ¡Á 2.1 mm) column and the eluent analyzed using a TSQ Vantage mass spectrometer with selected reaction monitoring. Matrix effects were characterized in addition to carryover, precision, linearity, recovery and functional sensitivity.
The simple and complex precision for the assay at multiple concentrations was ¡Ü 6.2 % . The assay has functional sensitivity of < 3 ng/ml, and is linear from 8.1 to 1978 ng/ml. Method comparison studies with a reference HPLC-MS/MS method show a slope of 0.84 with a Spearman coefficient of 0.99.
Based on the validation metrics, we have generated a sensitive and automated TFC-MS/MS method for docetaxel quantitation in serum.