Cost Effective Quantification of Asenapine Maleate in Rat Plasma: Application to Pharmacokinetic Studies by RP-HPLC with Photodiode Array

Cost effective method of reverse-phase high performance liquid chromatography (RP-HPLC) with photodiode array (PDA) detector was developed for the quantification of asenapine maleate (AM) as a typical antipsychotic drug in rat plasma. Separated AM from plasma was diluted with mobile phase and analysed directly with HPLC-PDA system. The separations were performed on a column packed with octylsilica (Symmetry C8 column, 250 x 4.6 mm, packed with 5-mu m particles) eluted with acetate buffer (pH 3.0)-acetonitrile mixture in a ratio of 35:65 v/v as the mobile phase, and the detection was performed at 269 nm. The standard curve was linear (r = 0.999) over a concentration range of 0.75 - 125 ng/mL. The intra- and inter-assay precisions were 0.2 and 0.4%, respectively, and the accuracy range was from 101.4 to 107.1%. The lower limit of quantitation, limit of quantitation and limit of detection in rat plasma were 0.75, 1.5, and 0.5 ng/mL, respectively. Maximum drug concentration (C-max) and time to the maximum concentration (T-max) in AM suspension treated rats were found to be 33.81 +/- 0.8 ng/mL and 1.5 +/- 0 h, respectively. The developed analytical method can be successfully applicable to the pharmacokinetic studies of asenapine maleate in rats and humans.