Pharmacokinetics and bioavailability of febrifugine in rat plasma determined by UPLC-MS/MS

Febrifugine, a potent quinazolinone compound derived from the Chinese herb Chang Shan (Dichroa febrifuga), exhibits diverse biological activities and has demonstrated anti-tumor effects by functioning as focal adhesion kinase (FAK) inhibitors. In this study, our objective was to establish a quantitative UPLC-MS/MS method and investigate the pharmacokinetic characteristics of febrifugine in rats following intravenous and oral administration routes. The rat tail vein was used for the collection of blood samples at designated time intervals following intravenous (2.0 mg kg-1) and oral (6.0 mg kg-1) administrations. Plasma samples were pretreated with acetonitrile as a protein precipitant and methylcytisine as an internal standard. Febrifugine concentration in rat plasma was determined using the UPLC-MS/MS method, and pharmacokinetic parameters were calculated using drug and statistics (DAS) software version for statistical analysis. The linear range of febrifugine in rat plasma was 1.5-1,500 ng mL-1, meeting the precision, recovery, and stability requirements for determination purposes. Febrifugine had a half-life (t1/2) of 3.2 +/- 1.6 h after administered via intravenous route, while t1/2 was 2.6 +/- 0.5 h after oral administration. The developed UPLC-MS/MS method is facile to operate while adhering to rigorous methodological verification standards, rendering it suitable for investigating the pharmacokinetics of febrifugine; and bioavailability was determined as 45.8%.