LC/MS/MS quantitation of an anti-cancer drug in human plasma using a solid-phase extraction workstation: application...

A liquid chromatographic/mass spectrometric (LC/MS/MS) method to quantitate an anti-cancer drug in human plasma was validated. The method has proven suitable for routine quantitation of the experimental anti-cancer compound at concentrations from 1 to 400 ng/ml. Retention times of the compound and internal standard (compounds I and II, respectively) were 1.8 and 2.1 min, respectively. No interfering endogenous peaks were observed throughout the validation process. Precision estimates for this approach were typically less than 5% relative standard deviation (RSD) across the calibration range. Other validation parameters studied included specificity, system reproducibility, limit of quantitation, accuracy, linear range, and stability of the compound and internal standard in plasma and injection solvent. This method was used to quantify drug for population pharmacokinetic studies.