[Determination of chrysosplenetin, metabolic inhibitor of artemisinin, in rat plasma by UPLC-ms/MS and study on its pharmacokinetics].

The study aimed to develop the assay of chrysosplenetin (CHR), a metabolic inhibitor of artemisinin by UPLC-MS/MS in rat plasma and investigate the pharmacokinetics parameters of CHR. The plasma samples were precipitated by acetonitrile to remove the proteins. Separation was carried out on a Shim-pack XR-ODS C,18(2. 0 mm x 100 mm, 2. 2 micromp.m) column using a mobile phase containing methanol-0. 1% formic acid (87:13) using by diazepam as internal standard. Mass spectrometer with electrospray ionization (ESI) operated in the positive ion mode was used for analysis. Total analysis time was 2 min. The assay was linear in the range 5-5 000 microg L-1 (r =0. 999 3) with recoveries in the range from 69. 0% to 81.2% and satisfied inter-, intra- precision and accuracy. CHR after oral administration is not easy to absorb with double or multimodal peak phenomenon. The t1/2 of CHR after intravenous injection was very short and that of low, medium, and high dosage was (17. 01 +/- 8. 06) , (24. 62 +/- 4. 59), (28. 46+/- 4. 63) min, respectively. The developed method was special, rapid, and sensitive for determination of CHR pharmacokinetics. [Key words] UPLC-MS/MS; chrysosplenetin; pharmacokinetics; plasma; rat