Quantification of rosuvastatin in human plasma by automated solid-phase extraction using tandem mass spectrometric detection

An assay employing automated solid-phase extraction (SPE) followed by high-performance liquid chromatography with positive ion TurboIonspray tandem mass spectrometry (LC–MS–MS) was developed and validated for the quantification of rosuvastatin (Crestor™) in human plasma. Rosuvastatin is a hydroxy-methyl glutaryl coenzyme A reductase inhibitor currently under development by AstraZeneca. The standard curve range in human plasma was 0.1–30 ng/ml with a lower limit of quantification (LLOQ) verified at 0.1 ng/ml. Inaccuracy was less than 8% and imprecision less than ±15% at all concentration levels. There was no interference from endogenous substances. The analyte was stable in human plasma following three freeze/thaw cycles and for up to 6 months following storage at both −20 and −70 °C. The assay was successfully applied to the analysis of rosuvastatin in human plasma samples derived from clinical trials, allowing the pharmacokinetics of the compound to be determined.