RESUMEN
ObjectiveTo determine the contents of four kinds of indole alkaloids （rhynchophylline， isorhynchophylline， corynoxeine， isocorynoxeine） in Uncaria by high-performance liquid chromatography-mass spectrometry-automatic internal standard （HPLC-MS-AIS）. MethodsChromatographic separation was performed using C18 column （3.0 mm×50 mm， 3.3 μm）， and the mobile phase， comprising 0.1% formic acid aqueous solution-acetonitrile （82∶18， V/V）， was eluted at a flow rate of 0.5 mL/min and column temperature of 30℃. Mass spectrometric detection was performed using an electrospray ionization source and positive multiple-reaction monitoring mode at a voltage capillary of 4 000 V. The mass-to-charge ratio （m/z） transition was 385.25/160.10 for rhynchophylline， 385.30/160.10 for isorhynchophylline， 383.25/160.15 for corynoxeine and 383.25/160.15 for isocorynoxeine， respectively. The injection volume was kept constant at 2 μL. ResultsThe linear concentration ranges of rhynchophylline， isorhynchophylline， corynoxeine and isocorynoxeine were 2.30~600.00 ng/mL （r=0.999 3）， 2.30~600.00 ng/mL （r=0.999 2）， 2.47~650.00 ng/mL （r=0.999 4） and 2.47~650.00 ng/mL （r=0.999 2）， respectively. The relative standard deviation （RSD） of precision and stability were all lower than 5.00%， the accuracy ranged from 92.40% to 104.10%， and the average recovery was 95.90%~104.60%. ConclusionHPLC-MS-AIS method is simple and accurate for the determination of four kinds of alkaloids in Uncaria， and can be used as a new method for quality control of Uncaria.
RESUMEN
ObjectiveTo develop a two-dimensional high-performance liquid chromatography （2D-HPLC） for simultaneous determination of the contents of four kinds of Uncaria alkaloids： rhynchophylline， isorhynchophylline， corynoxeine and isocorynoxeine. MethodsThe 2D-HPLC apparatus was comprised of a first chromatographic column in version Aston SC2 （3.5 mm×25 mm， 5 μm）， an intermediate column in version Aston SH C18 （3.5 mm×10 mm， 5 μm）， and an analytical column in version Aston SCB （4.6 mm×125 mm， 5 μm）. The mobile phase of the first and second liquid chromatography system were CAA-1 and mixed mobile phase （V BPI-1 basic mobile phase ∶ V MPI-1 mobile phase ∶ V OPI-1 organic mobile phase = 45∶14∶41）. The chromatographic parameters included a flow rate of 1.0 mL/min， a column temperature of 40℃， a wavelength of 254 nm， an injection volume of 500 μL and a detection time of 9.5 min. ResultsThe linear ranges of rhynchophylline， isorhynchophylline， corynoxeine and isocorynoxeine were 9.77~10 000.00 ng/mL （r=0.999 6）， 10.74~11 000.00 ng/mL （r=0.999 7）， 10.74~11 000.00 ng/mL （r=0.999 7）， 10.74~11 000.00 ng/mL（r=0.999 6）， respectively. The relative standard deviation （RSD） of precision， stability and repeatability were all less than 5.00%. The accuracy was 95.20%~104.01%， and the recovery rate was 93.63%~101.38%. ConclusionThe 2D-HPLC developed for simultaneous determination of four kinds of alkaloids in Uncaria is simple and accurate， which can be used as a new method for quality control of Uncaria.