Rapid Determination of Pitavastatin in Plasma by LC-ESI-MS/MS

OBJECTIVE To set up a rapid and sensitive LC-ESI-MS/MS method for the determination of pitavastatin in plasma. METHODS Pitavastatin was extracted with ethyl acetate-dichloromethane. The residues were analyzed with a LC-MS/MS system (Agilent Eclipse Plus C₁₈ column, 4.6 mm×150 mm, 3.5 µm) with the mobile phase of methanol-0.005 mol·L^-1 ammonium formate aqueous solution-acetonitrile-1% formic acid(7.5∶2.5∶70∶20), with a flow rate of 0.5 mL·min^-1, temperature: 40 ℃. Selected reaction monitoring (SRM) using the precursor to production combinations of m/z 422.2→290.2 and m/z 482.2→258.2 was performed to detect pitavastatin and the internal standard, respectively. RESULTS The RSDs of average recovery of different concentration of pitavastatin(80, 50, 0.25 μg·L^-1) were less than 15%. The calibration curves for pitavastatin had good linearity over the range of 0.1-100 μg·L^-1, r=0.996 0. CONCLUSION The method provides a sensitive, accurate, precise and reliable analytical procedure for clinical monitoring of pitavastatin plasma and its phamacokinetic studies.