Development and validation of a rapid and sensitive UHPLC–MS/MS method for the determination of paliperidone in beagle dog plasma

In order to evaluate the pharmacokinetic profile of paliperidone extended-release tablets in vivo, a simple and rapid ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method was developed and validated for the determination of paliperidone in beagle dog plasma. Paliperidone and diazepam (internal standard) were extracted from plasma samples with diethyl ether, and then separated on a C18 column (2.1 × 50 mm, 2.6 μm) under gradient elution with methanol–0.1% formic acid at a flow rate of 0.3 ml/min. The compounds were detected using a triple-quadrupole mass spectrometer equipped with an electrospray ionization (ESI) source. The validated method was linear over the concentration range of 1.00–1000.00 ng/ml and the lower limit of quantitation was 1.00 ng/ml. The intra-day and inter-day precision values were not more than 15% (relative standard deviation < 20% at low levels), while the accuracy was within ±10% of nominal values. The validated UHPLC–MS/MS method was successfully applied to an oral pharmacokinetic study of paliperidone extended-release tablets in a beagle dog.