Method validation of amlodipine and atorvastatin by liquid chromatography–mass spectrometry (LC–MS) method in human plasma

A rapid and selective liquid chromatography–mass spectrometry (LC–MS) method was developed for the evaluation of amlodipine and atorvastatin in human plasma. Detection of analytes was assigned by tandem mass spectrometry with electrospray ionization interface in positive ion mode was applied under the multiple-reaction monitoring mode (MRM). Analytes were extracted from plasma by simple liquid–liquid extraction technique using ethyl acetate. The reconstituted samples were chromatographed on C18 column by pumping acetonitrile–water (10 mM CH3COONH4, pH 3.0) = 70:30 (v/v) at a flow rate of 0.15 mL/min. The standard curves were assigned to be linear in the range of 0.2–20 ng/mL for atorvastatin and 0.1–10 ng/mL for amlodipine with mean correlation coefficient of ≥0.999 for each analyte. The intra-day and inter-day precision and accuracy results were well within the acceptable limits. The urbanized evaluate method was successfully applied to validation of amlodipine and atorvastatin in human plasma.