Quantification of propranolol in rat plasma by LCMS/MS using tramadol as an internal standard : Application to pharmacokinetic studies in TAA-induced liver fibrotic rats

Abstract

A simple, rapid and selective liquid chromatography coupled with tandem mass spectrometry (LCMS/MS) is developed and validated for quantification of propranolol without the sample extraction stepin rat plasma using tramadol as an internal standard (IS). The analytes are separated using an isocraticmobile phase which consist of methanol and 10 mm ammonium formate (70/30, v/v) on an isocratic UKC18(Imtakt Unison 2.0 × 50 mm, 3 μm) column and was analyzed by MS/MS in the multiple reactionmonitoring (MRM) mode using the transitions of respective (M+H)+ ions, m/z 260.0→116.2 and m/z264.2→58.2 for quantification of propranolol and IS, respectively. The standard calibration curvesshowed good linearity within the range of 2.0 to 800.0 ng/ml (r2 = 0.999, 1/x2 weight). The lower limit ofquantification (LLOQ) was 2 ng/ml. The retention time of propranolol and IS were 1.12 and 0.939 minwhich means that it is the potential for the high-through put potential of the proposed method. Inaddition, no significant metabolic compounds were found to interfere with the analysis. Acceptableprecision and accuracy were obtained for the concentrations over the standard curve range. Thevalidated method was successfully applied for the pharmacokinetic studies after 2 mg/kg of propranololHCl in the thioacetamide (TAA)-induced fibrotic rats.