LC-MS-MS determination of pregabalin in human plasma

A rapid, sensitive and specific method to quantify pregabalin in human plasma using metaxalone as the internal standard is described. Sample preparation involved simple protein precipitation by using acetronitrile as solvent. The extract was analyzed by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC-MS-MS). Chromatography was performed isocratically on Thermo Hypurity C-18 5 mu m analytical column, (50 mm x 4.6 mm i.d.). The assay of pegabalin was linear calibration curve over the range 10.000-10000.000 ng mL(-1). The lower limit of quantification was 10.000 ng mL-1 in plasma. The method was successfully applied to the bioequivalence study of pregabalin capsules (150.0 mg) administered as a single oral dose.