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A selective and sensitive ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method was developed and validated for the determination of three triterpenoid saponins isolated from Astragalus membranaceus leaf extract. In this article, a method for simultaneous determination of Huangqiyenin A, Huangqiyenin E, and Huangqiyenin K was established for the first time. The method was successfully applied to the pharmacokinetic study of Astragalus membranaceus leaf extract after oral administration. Liquid–liquid extraction was applied to plasma sample preparation. Multiple reaction monitoring mode with an electrospray ion source in positive electrospray ionization was chosen to quantify the analytes. Chromatographic separation was performed on a Waters HSS T3 column, using gradient elution with a mobile phase composed of acetonitrile and 5 mM ammonium acetate/water. The pharmacokinetic results showed that all three compounds had the characteristics of rapid absorption‐slow metabolism trend. The time of maximum plasma concentration of Huangqiyenin A is higher than Huangqiyenin E and Huangqiyenin K. And the maximum plasma concentration of Huangqiyenin A is higher as well. The pharmacokinetic results revealed the pharmacokinetic characteristics of the three analytes in rat plasma, which could provide a helpful reference for the further study of Astragalus membranaceus leaf extract. [ABSTRACT FROM AUTHOR]

A sensitive and rapid liquid chromatography with tandem mass spectrometry method has been developed for simultaneous determination of berberine (I), jateorhizine (II), palmatine (III), tetrahydropalmatine (IV), phellodendrine (V), protopine (VI) and columbamine (VII) in rat plasma after oral administration of Phellodendri chinensis cortex extraction. The plasmas were extracted by liquid‐liquid extraction. The tandem mass spectrometric detection was performed in the multiple reaction monitoring mode in the positive ionization. The intra‐ and interday precisions and accuracies were in range from −12.18 to 13.21%. Mean absolute recoveries of all analytes and internal standard were between 78.6 and 98.9%. The seven alkaloids were proven to be stable during sample storage and analysis procedures. The established method was validated and successfully applied to pharmacokinetics study in rat plasma after oral administration of Phellodendri chinensis cortex extract. The t1/2 of palmatine, columbamine, pellodendrine, berberine, tetrahydropalmaine, jatrorrhizine, and protopine were 5.16, 5.96, 7.18, 19.84, 6.28, 7.08, 6.90 h, respectively. The seven compounds could be rapidly absorbed into blood (time for maximal concentration, 1.80–1.93 h). This study could establish a foundation for further research of Phellodendri chinensis cortex and might provide more useful information to guide the clinical usage. [ABSTRACT FROM AUTHOR]

Abstract: A sensitive, specific, and accurate ultra high‐performance liquid chromatography with electrospray ionization tandem mass spectrometry method was developed and validated for the simultaneous quantification of purpurin, munjistin, mollugin, and alizarin from Qianzhi capsules in rat plasma. Chromatographic separation was performed on an Agilent Eclipse Plus C18 RRHD column with a mobile phase consisting of methanol and 5 mM ammonium acetate/water with gradient elution. The analytes were quantified on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring mode and switching the electrospray ion source polarity with positive electrospray ionization in a single run. Samples were pretreated by liquid–liquid extraction with cyclohexane. The intra‐ and interday precision and accuracy of the assay were within acceptable ranges. Matrix effects for all of the analytes were between 90.16 and 100.21%. The average recovery ranged from 75.38 to 88.96%. This method was successfully applied to study the pharmacokinetic parameters of the four compounds in rat plasma after oral administration of Qianzhi capsules. Four quinones could be rapidly absorbed into blood (tmax, 0.80–1.93 h) and eliminated relatively slowly (t1/2, 8.07–11.97 h). The results might be helpful for guiding the clinical application of Qianzhi capsules in the future. [ABSTRACT FROM AUTHOR]

A specific, simple, and sensitive ultra high performance liquid chromatography with tandem mass spectrometry method utilizing the Triple Quad system has been developed and validated for the simultaneous determination and pharmacokinetic study of four triterpenoid components of Acanthopanax sessiliflorus in rat plasma. The components are 22-α-hydroxychiisanogenin, chiisanogenin, (1R,11α)1,4-epoxy-11-hrdroxy-3,4-secolupane-20(30)-ene-3,28-dioic acid, and 22-α-hydroxychiisanoside. Sample preparation involved a liquid-liquid extraction of the analytes with ethyl acetate. Chromatographic separation was accomplished using an Agilent SB-C18 column (1.8 μm, 2.1 mm × 50 mm) with 2.0 min isocratic elution. The compounds were detected with a triple quadrupole tandem mass spectrometer in multiple reaction monitoring mode and an ESI source in negative mode. The method was linear for all analytes over the investigated range, with all determined correlation coefficients exceeding 0.9906. The limit of quantification of each analyte was lower than 1 ng/mL. The intraday and interday precisions were less than 14.9%, and the accuracy ranged from -10.2 to 11.8%. The mean recoveries of the analytes were higher than 80.0%, and the matrix effects were between 100.4 and 107.1%. These results may contribute to determining the mechanism of action and guiding the clinical application of Acanthopanax sessiliflorus. [ABSTRACT FROM AUTHOR]