A simple and sensitive assay for the quantitative analysis of paclitaxel and metabolites in human plasma using liquid chromatography/tandem mass spectrometry.

A sensitive and specific LC-MS/MS assay for the determination of paclitaxel and its 3'p- and 6-alpha-hydroxy metabolites is presented. A 200 microL plasma aliquot was spiked with a 13C6-labeled paclitaxel internal standard and extracted with 1.0 mL tert-butylmethylether.

Phase I clinical and pharmacokinetic study of kahalalide F in patients with advanced androgen refractory prostate cancer.

Purpose: The purpose is to determine the maximum tolerated dose, profile of adverse events, and dose-limiting toxicity of Kahalalide F (KF) in patients with androgen refractory prostate cancer. Furthermore, the pharmacokinetics after KF administration and preliminary antitumor activity were evaluated. KF is a dehydroaminobutyric acid-containing peptide isolated from the marine herbivorous mollusk, Elysia rufescens.

Stable isotopically labeled internal standards in quantitative bioanalysis using liquid chromatography/mass spectrometry: necessity or not?

It appears to be a general belief that stable isotopically labeled (SIL) internal standards yield better assay performance results for quantitative bioanalytical liquid chromatography/mass spectrometry (LC/MS) assays than does any other internal standard. In this article we describe our experiences with structural analogues and SIL internal standards and their merits and demerits. SIL internal standards are the first choice, but deuterium-labeled compounds may demonstrate unexpected behavior, such as different retention times or recoveries, than the analyte.

A simple and sensitive assay for the quantitative analysis of paclitaxel in human and mouse plasma and brain tumor tissue using coupled liquid chromatography and tandem mass spectrometry.

The development and validation of an assay for the determination of paclitaxel in human plasma, human brain tumor tissue, mouse plasma and mouse brain tumor tissue is described. Paclitaxel was extracted from the matrices using liquid-liquid extraction with tert-butyl methyl ether, followed by chromatographic analysis using an alkaline eluent. Positive ionization electrospray tandem mass spectrometry was performed for selective and sensitive detection.