Simultaneous determination of 11 alkaloids in rat plasma by LC-ESI-MS/MS and a pharmacokinetic study after oral administration of total alkaloids extracted from Naucleaofficinalis.

Nauclea officinalis, a widely used Li medicine, has been used for the treatment of cold, fever, bronchitis, pneumonia, acute tonsillitis, and other ailments. Modern pharmacological studies have demonstrated that the most abundant and active components in N. officinalis are alkaloids, which possess various biological properties such as antibacterial and antitumor activities. To investigate the phytochemical profile of a selected group of alkaloids from the N. officinalis total alkaloids, and to determine the chemical profile of the alkaloids extracted from rat plasma. Further investigation was conducted to determine the pharmacokinetic behaviors of 11 selected major alkaloids, including pumiloside, naucleoxoside A, naucleoxoside B, nauclefine, angustidine, angustoline, (3S,19S)-3,14-dihydroangustoline,[α]D20: (-)191°, (3S,19R)-3,14-dihydroangustoline, [α]D20: (-) 294.7°, strictosamide, angustine, and 3,14-dihydroangustine. N. officinalis total alkaloids were extracted with 79% ethanol and enriched with AB-8 macroporous resin. The phytochemical profile of alkaloids from the N. officinalis total alkaloids and the chemical profile of the alkaloids extracted from rat plasma were first analyzed by UPLC-Q-TOF-MS/MS. A simple, convenient, and sensitive LC-ESI-MS/MS method was subsequently developed and validated for the simultaneous determination of major active alkaloids in rat plasma after oral administration of N. officinalis total alkaloids. After addition of an internal standard (verapamil), plasma samples were pretreated first by protein precipitation with methanol and then underwent liquid-liquid extraction with ethyl acetate. Chromatographic separation was achieved using a Waters BEH C18 column (2.1 mm × 100 mm, 1.7 μm) at 30 °C, with gradient elution using a mobile phase consisting of 0.1% formic acid aqueous solution (A) and acetonitrile (B), a flow rate of 0.2 mL/min, and a total run time of 30 min. The detection was performed using an electrospray ionization triple quadrupole tandem mass spectrometer with multiple reaction monitoring and positive ionization mode. Based on the fragmentation patterns of 11 authentic alkaloids and previous reports, 55 alkaloids were identified or tentatively identified in the N. officinalis total alkaloids. Among them, 25 alkaloids were absorbed through the gastrointestinal tract in rats after administration of the N. officinalis total alkaloids. The 11 alkaloids were selected for quantitative analysis. The established quantitative method was fully validated and proved to be sensitive and specific. Satisfactory linearity of the 11 alkaloids obtained in the respective concentration ranges (r > 0.9931). The lower limits of quantification for strictosamide was 20.86 ng/ml, and the other ten alkaloids were all less than 4.47 ng/ml in rat plasma. The intra-and inter-day precision was less than 15% for all 11 alkaloids in terms of relative standard deviation, and the accuracies ranged from -11.4% to 11.1% in terms of relative error. Extraction recovery, matrix effect, and stability were within the required limits in rat plasma. The validated method was successfully applied to investigate the pharmacokinetics of the 11 alkaloids in rat plasma after oral administration of N. officinalis total alkaloids. Eleven alkaloids were rapidly absorbed to achieve a maximum plasma concentration with Tmax from 0.25 h to 1.5 h after oral administration. The pharmacokinetic parameters and plasma concentration-time profiles will prove valuable in pre-clinical and clinical investigations on the disposition of N. officinalis total alkaloids.

Wang G ，Wang H ，Lin Z ，Hou L ，Wang JY ，Sun L ... -  《-》

The rapid profiling and simultaneous determination of 12 major alkaloids in Nauclea officinalis by UPLC-Q-TOF-MS and HPLC-ESI-MS/MS.

Wang G ，Wang H ，Liu H ，Wang Y ，Lin Z ，Sun L ... -  《-》

Simultaneous determination of six alkaloid components in rat plasma and its application to pharmacokinetic study of Danmu preparations by an ultra fast liquid chromatography-electrospray ionization-tandem mass spectrometry.

Danmu injection and Danmu tablet are two widely used traditional Chinese medicine made of Nauclea officinalis (commonly known as Danmu), in which the alkaloids are the major active substances. In this paper, an ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method was developed for simultaneous determination and the pharmacokinetic characteristics study of six main active alkaloids (naucleamide A-10-O-β-d-glucopyranosid, naucleamide G, pumiloside, 3-epi-pumiloside, strictosamide and vincosamide) of the two above-mentioned Danmu preparations in rat plasma. In the course of the experiment, following sample preparation by protein precipitation with methanol-ethyl acetate (2:1, v/v), the nitrogen-dried extraction was reconstituted in methanol and assayed on a C18 column using a gradient elution program with mobile phase consisting of acetonitrile and water containing 0.1% formic acid. The MS detection was performed in positive ionization mode with selected ion transitions. The established method was fully validated and proved to be sensitive and specific with lower limits of quantification (LLOQs) all less than 0.32ng/mL in rat plasma and matrix effects ranged from 88.87 to 108.27%. Good linearities of six alkaloids were obtained in respective concentration ranges (r(2)>0.995). The average extract recoveries for each compound at three quality control concentration levels were no less than 79.70%, and the precision and accuracy were within the acceptable limits. The validated method was successfully applied to the pharmacokinetic study of six alkaloid components of Danmu injection and tablet in rat plasma. The obtained results may be helpful to reveal the action mechanism and guide the clinical application of Danmu preparations.

Yin R ，Chen J ，Zhao Y ，Jia X ，Zhang Z ，Feng L ，Wang H ，Wang J ，Zhu F ... -  《-》

Simultaneous determination of seven alkaloids in rat plasma by UFLC-MS/MS and its application to a pharmacokinetic study after oral administration of Cerebralcare Granule.

An ultra fast liquid chromatography-tandem mass sepectrometry (UFLC-MS/MS) method was developed for simultaneous determination of seven active alkaloid components (tetrahydropalmatine, corydaline, α-allocryptopine, tetrahydroberberine, tetrahydrocoptisine, tetrahydrocolumbamine and dehydrocorydaline) in rat plasma after oral administration of Cerebralcare Granule. Plasma samples were pretreated by protein precipitation with acetronitrile containing the internal standard diazepam. Chromatographic separation was achieved on a Phenomenex Kinetex C18 column (100×2.1mm, 2.6μm) with gradient elution using mobile phase consisting of acetonitrile -0.1% formic acid in water at a flow rate of 0.3mL/min. The detection was performed on an electrospray ionization triple quadrupole tandem mass spectrometer using multiple reaction monitoring (MRM) with positive ionization mode. The established method was fully validated and proved to be sensitive and specific with lower limits of quantification (LLOQs) all less than 0.0265ng/mL in rat plasma. Good linearities of seven alkaloids were obtained in respective concentration ranges (r>0.9923). The intra- and inter-day precisions were below of 15% for all the seven alkaloids in terms of relative standard deviation (RSD), and the accuracies were ranged from -2.7% to 8.3% in terms of relative error (RE). Extraction recovery, matrix effect and stability were within the required limits in rat plasma. The validated method was successfully applied to investigate the pharmacokinetics of the seven alkaloids in rat plasma after oral administration of Cerebralcare Granule (CG).

Xiaowen L ，Ling T ，Yunfei L ，Guoxiang S ，Dailin Y ，Herry S ... -  《-》

UHPLC-ESI-MS/MS determination and pharmacokinetic study of two alkaloid components in rat plasma after oral administration of the extract of Corydalis bungeana Turcz.

Corynoline and acetycorynoline are active compounds of Corydalis bungeana Turcz. with various pharmacological effects such as sedation, anti-leptospira and liver injury protection effects. A specific, simple and sensitive UHPLC-ESI-MS/MS method was developed and validated for the pharmacokinetic study of corynoline and acetycorynoline in rat plasma. Corynoline and acetycorynoline were extracted from plasma samples by liquid-liquid extraction. The analysis was carried out on an Agilent SB-C18 column (1.8 μm, 50 mm×2.1mm) with the mobile phase of acetonitrile-0.1% formic acid (80:20, v/v). The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI) source in positive mode. The current UHPLC-ESI-MS/MS assay was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery and stability. The lower limits of quantification were 0.10 ng/mL for corynoline and 0.353 ng/mL for acetycorynoline. Intra-day and inter-day precision were less than 12.3% and accuracy ranged from 0.18% to 14.9%. The mean extraction recoveries of analytes and internal standard (IS) from rat plasma were all more than 76.2%. This validated method was successfully applied to pharmacokinetic study in rats after oral administration of corynoline, acetycorynoline and the extract of Corydalis bungeana Turcz.

Yang C ，Xiao Y ，Wang Z ，Wang S ，Chen L ，Wu L ，Liu G ... -  《-》