A rapid and sensitive LC–MS/MS assay for the quantitation of deacetyl mycoepoxydiene in rat plasma with application to preclinical pharmacokinetics studies

The purpose of this study was to develop and validate a high-performance liquid chromatographic–tandem mass spectrometric (LC–MS/MS) method for analysis of the deacetyl mycoepoxydiene in rat plasma. The analyte and internal standard (I.S.), benorilate, were extracted from rat plasma by precipitation protein and separated on a C18 column using acetonitrile–0.5% formic acid as mobile phase. Detection was performed using a turbo-spray ionization source and mass spectrometric positive multi-reaction-monitoring-mode (+MRM) at an ion voltage of +4800 V. The assay was linear over the concentration range 5–5000 ng/mL with the lowest limit of quantification (LLOQ) of 5 ng/mL. The method also afforded satisfactory results in terms of the sensitivity, specificity, precision (intra- and inter-day, RSD < 5.8%), accuracy, recovery as well as the stability of the analyte under various conditions. The method was successfully applied to a preclinical pharmacokinetic study in rats after a single intravenous administration of deacetyl mycoepoxydiene 10 mg/kg.