| Objective Establishment of two-dimensional high performance liquid chromatography (2D-HPLC) method for simultaneous determination of rhynchophylline, isorhynchophylline, corynoxeine and isocorynoxeine. Methods Aston SC2 (3.5 mm × 25 mm, 5 μm) is as one dimensional column, Aston sh C18 (3.5 mm × 10 mm, 5 μm) is as Intermediate column, Aston SCB (4.6 mm × 125 mm, 5 μm) is as analysis column, the one-dimensional mobile phase is CAA-1, the analysis mobile phase is BPI-1:MPI-1:OPI = 45:14:41, the flow rate is 1.0 mL / min, the column temperature is 40 ℃, the detection wavelength is 254 nm, and the injection volume is 500 μL. The analysis time was 9.5 min. Results The linear ranges of rhynchophylline, isorhynchophylline, corynoxeine and isocorynoxeine were 9.77~10 000 ng/mL (r=0.999 6), 10.74~11 000 ng/mL (r=0.999 7), 10.74~11 000 ng/mL (r=0.999 7), 10.74~11 000 ng/mL (r=0.999 6). The RSD of precision, stability and repeatability were lower than 5.00%, the accuracy was 95.20%-104.01%. The method recoveries were 95.9%~104.6%. Conclusion 2D-HPLC method is simple and accurate for the determination of four alkaloids in uncaria, and can be used as a new method for quality control of uncaria. |