No abstract

Polyphyllin VII is an isoprene saponin extracted from Rhizoma paridis, and it can effectively suppress tumor initiation, growth, and metastasis. In this study, we aim to develop and validate an LC-MS/MS method for the quantification of polyphyllin VII in rat plasma using digoxin as the internal standard (IS). The plasma samples were precipitated with methanol, and the samples were separated on an ACQUITY BEH C 18 column (2.1 Â 50 mm, 1.7 μm). The mobile phase consisted of 0.1% formic acid solution and acetonitrile. The detection was performed in the multiple reactions monitoring mode, with the precursor-to-product transitions of m/z 1075.4 > 883.3 for polyphyllin VII and m/z 779.4 > 649.6 for the IS. The method showed excellent linearity over the concentration range of 0.5-1000 ng/ml, with a correlation coefficient of 0.9996 (r = 0.9996). The lower limit of quantification was 0.5 ng/ml. The inter-and intra-day accuracy (relative error) ranged from À4.8 to 5.9%, and precision (relative standard deviation) was < 9.0%. The assay showed high extraction recovery, ranging from 90.6 to 95.6%. Polyphyllin VII was demonstrated to be stable under the storage conditions. The validated LC-MS/MS method was successfully applied to the pharmacokinetic study of polyphyllin VII in rats after oral, intraperitoneal, and intravenous administrations. The pharmacokinetic results indicated that polyphyllin VII showed low oral (5.86%) bioavailability and moderate (38.81%) intraperitoneal bioavailability.

Swertia cincta, a plant of the genus Swertia in Gentianceae, “heat-clearing” and detoxifying effects that normalize the gallbladder function in the treatment of jaundice. Although numerous studies about Swertia cincta have been performed, the absorption and pharmacokinetic behaviors remain unclear. In this study, the compounds of Swertia cincta in serum, bile, feces, and urine of rats were analyzed using a ultra-high-performance liquid chromatography-tandem mass spectrometry. A total of 9 prototype components and 48 metabolites were detected in biological samples. Furthermore, we determined the main components absorbed in the blood of Swertia cincta and established a method for simultaneously determining these components (sweroside, swertiamarin and gentiopicroside) in positive ionization mode within 6 min. The quantitative method was successfully applied for the multiple-component pharmacokinetic study of Swertia cincta.