astragaloside-ii and formononetin

A sensitive and reliable ultra-pressure liquid chromatography with tandem mass spectrometry (UPLC-MS) was developed and validated for simultaneous quantification of six main bioactive components, i.e., calycosin-7-O-β-D-glucoside, ononin, calycosin, formononetin, astragaloside IV, and astragaloside II in rat plasma after oral administration of the 95 % ethanol extraction from Radix Astragali. Plasma samples were extracted with Waters Oasis(TM) HLB 1 cc (30 mg) Extraction Cartridges (SPE) separated on an UPLC™ BEH C18 column and detected by MS with electro spray ionization interface in positive selective ion monitoring mode. Calibration curves offered linear ranges of two orders of magnitude with r (2) > 0.99. The method had the lower limit quantification of 1.30, 0.73, 1.17, 2.33, 0.63, and 0.83 ng/mL for ononin, calycosin, calycosin-7-O-β-D-glucoside, formononetin, astragaloside IV, and astragaloside II, respectively, with precision less than 10 %. The RSD of intra- and inter-day variations ranged from 1.66 to 6.46 and 3.39 to 6.58 %. This developed method was applied subsequently to pharmacokinetic studies of the six compounds in rats successfully. The proposed method was for the first time to compare the pharmacokinetic difference between calycosin-7-O-β-D-glucoside and calycosin in rat plasma, so as between ononin and formononetin, and studied to the astragaloside II pharmacokinetics in rat plasma.

Topics: Administration, Oral; Animals; Astragalus propinquus; Blood Chemical Analysis; Chromatography, High Pressure Liquid; Drugs, Chinese Herbal; Glucosides; Isoflavones; Rats; Rats, Sprague-Dawley; Saponins; Tandem Mass Spectrometry; Time Factors; Triterpenes

Bu-yang-huan-wu-tang (BYHWT) is a popular Traditional Chinese Medicine formula consisting of seven herbal medicines (Astragalus membranaceus, Angelica sinensis, Paeonia lactiflora, Ligusticum chuanxiong, Carthamus tinctorius, Amygdalus persica and Pheretima aspergillum), that has been used in China for centuries to overcome stroke-induced disability. To ensure the consistency of quality, a reliable analytical method is required, therefore, we developed a liquid chromatography with tandem mass spectrometry (LC-MS/MS) method for quantitative analysis of the major constituents in BYHWT. The herbal ingredients consisting of the cycloartane-type triterpene glycosides of astragaloside I, astragaloside II and astragaloside IV; isoflavones of formononetin, ononin calycosin, calycosin-7-O-β-d-glucoside; ligustilide and paeoniflorin were separated on a C18 column with gradient elution of methanol/10 mM ammonium acetate buffer-formic acid (100:0.1, v/v). This study was performed by a mass spectrometer using electrospray ionization (ESI) with positive ionization ions monitored in the multiple reaction-monitoring (MRM) mode. The linearity, accuracy, precision, limit of detection (LOD) and lower limit of quantification (LLOQ) were validated for this quantification method, and the sensitivity, reliability and reproducibility were all confirmed. The experiments provided a good method for analyzing BYHWT extracts. This study also quantitated the active components in various brands of commercially available products. The results indicated that the pharmaceutical industrial products of BYHWT exhibited considerable variation in their contents of the herbal compounds.

Topics: 4-Butyrolactone; Benzoates; Bridged-Ring Compounds; Chromatography, High Pressure Liquid; Digoxin; Drugs, Chinese Herbal; Glucosides; Humans; Isoflavones; Limit of Detection; Medicine, Chinese Traditional; Monoterpenes; Reproducibility of Results; Saponins; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry; Triterpenes