Determination and Pharmacokinetics of PA-824 in the Plasma of Beagle Dogs by HPLC-MS/MS / 中国药师

ABSTRACT

Objective: To establish a high performance liquid chromatography-tandem mass spectrometric method ( HPLC-MS/MS) method for the determination of PA-824 in the plasma of Beagle dogs, and study the pharmacokinetics of PA-824 in Beagle dogs. Methods:Carbamazepine was used as the internal standard, and the plasma samples were pretreated with ethyl acetate for the liquid-liquid extraction of PA-824. An Eclipse Plus C18 column (100 mm × 2. 1 mm, 3. 5 μm) was used with the mobile phase consisting of methanol-water (9010). The flow rate was 0. 6 ml·min-1 and the column temperature was 30 ℃. The injection volume was 5 μl and the sample analysis time was 5 min. The determination was performed with an electrospray ionization ( ESI) source in the positive multiple reaction monitoring (MRM) mode. The ion pairs were m/z 360. 1→m/z 175. 0 (collision energy of 35, solution cluster volt-age of 65) for PA-824 and m/z 237. 2→m/z 194. 0 (collision energy of 28, solution cluster voltage of 83) for carbamazepine. After the oral administration, PA-824 in plasma was measured at different time points, and then the pharmacokinetic parameters were calcu-lated by DAS 2. 0 software. Results: PA-824 showed a good linear relationship within the range of 50-10000 ng · ml-1 ( r =0. 9991). The recovery was 97. 7%-105. 1%, and the RSDs of intra-day and inter-day were less than 5. 0%. At three different dosa-ges (100, 200 and 500 mg) of PA-824, AUC0-twere (5735. 18 ± 1918. 76),(11548. 47 ± 1838. 04) and (21987. 88 ± 4587. 58) ng·min·ml-1,t1/2 were(14.17 ±5.97),(11.11 ±4.39) and (13.13 ±5.46)h,and Cmaxwere(626.66 ±188.48),(2399.13 ± 516.51) and (4861.33 ±2253.61)ng·ml-1, respectively. Conclusion:The method is simple, accurate, rapid and reproducible, and suitable for the pharmacokinetic study of PA-824 in the plasma of Beagle dogs.