摘要
The purpose of the study is to develop an ultra performance liquid chromatographytandem mass spectrometry(UPLCeMS/MS)to determinate the concentration of azilsartan in the dog plasma.After precipitated by methanol,the plasma sample containing azilsartan and diazepam(internal standard,IS)was determined by UPLCeMS/MS.The mobile phase consisted of acetonitrile-water was pumped at a flow rate of 0.3 ml/min in gradient elution.Kinetex 2.6 m XB-C18 column(502.1 mm,100Å;Phenomenex,USA)were used for LC separations.The column temperature was 30℃ and the injection volume was 5 ml.The electrospray ionization(ESI)and multiple reaction monitoring(MRM)were applied at the transitions of m/z 457/279(azilsartan)and m/z 285/193(diazepam),respectively.The developed method was identified a good linearity over a concentration range of 2.5e5000 ng/ml.The lower limit of quantitation(LLOQ)was 2.5 ng/ml.The intraday and inter-day precision(relative standard deviation,RSD%)were less than 10%and accuracy(relative error,RE%)was less than 5%at three quality control levels.The extraction recovery of azilsartan at three quality control levels were 82.41±0.68%,98.66±11.00%,102.43±0.82%.And the recovery for IS(100 ng/ml)was 91.75±0.54%.A validated UPLCeMS/MS method was firstly developed for the quantification of azilsartan in dog plasma and it was applied to the pharmacokinetics study.
