A simple sensitive UFLC-MS/MS method for the simultaneous quantification of artesunate, dihydroartemisinin and quercetin in rat plasma and its application to pharmacokinetic studies.

An ultrafast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method was developed for the simultaneous estimation of artesunate (ART), dihydroartemisinin (DHA, an active metabolite of ART) and quercetin (QRT) in rat plasma. The separation was achieved using a Zorbax C column (3 μm, 50 mm × 4.6 mm) as a stationary phase with a mobile phase of 0.1% formic acid (10% by volume) and methanol (90% by volume) at a flow rate of 0.4 mL min and an injection volume of 10 μL. Artemisinin (ATM) was used as the internal standard (IS). Mass detection was performed by electrospray ionization (ESI)-tandem mass spectrometry multiple reaction monitoring (MRM) in positive mode except for QRT, where negative ionization was used. The extraction recoveries of ART, DHA, and QRT from plasma were found to be 91.05-99.62%, 95.12-98.56% and 89.35-98.90%, respectively. The developed method was validated and successfully applied to the quantitative analysis of ART, DHA and QRT in plasma samples after the oral administration of ART and ART-QRT pure drugs to rats at the dose of 5 mg kg each. The results reveal that the developed method can be further used for the quantification of the proposed combination drugs in nanoformulations.