A rapid and sensitive UPLC–MS/MS method for quantitative determination of arformoterol in rat plasma, lung and trachea tissues

Abstract A rapid and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC–MS/MS) method was developed and fully validated for determination of arformoterol in rat plasma, lung and trachea tissues. The chromatographic separation was performed on an Agilent XDB C8 column with gradient elution by using acetonitrile and 0.1% formic acid water. The method presented high sensitivity (LLOQ of 1.83 pg/mL for plasma and 3.90 pg/mL for lung and trachea tissue homogenates) and great linearity over the range of 1.83–458 pg/mL for plasma, 13.9–1560 pg/mL for lung and trachea tissue homogenates. No carry over effect and matrix effect were observed. The intra- and inter-day precision/accuracy were within ±15% at three quality control concentration levels. This robust method was successfully applied to the pharmacokinetic, lung and trachea tissue distribution study after inhalation administration of arformoterol tartrate inhalation solution (50 μg/kg). The in vivo information indicate that arformoterol can be rapidly absorbed into blood through respiratory systems, lung and trachea tissue maintain a certain amount of arformoterol in 1 h after dosing.