Simultaneous Determination of Five Alkaloids in Corydalis Decumbentis Rhizoma by Microemulsion Liquid Chromatography

Objective: To develop the accurate and rapid method for determination of jatrorrhizine,palmatine,berberine,tetrahydropulmatine and protopine in Corydalis Decumbentis Rhizoma by microemulsion liquid chromatography( MELC). Method: The mobile phase was microemulsion that was optimized by inspecting the influence factors of separation and retention time. The optimized microemulsion was 2% sodium dodecyl sulfate-0. 5% noctyl alcohol-4% nbutanol-phosphate buffer( pH was adjusted by phosphoric acid to 4. 0). Sinochrom ODS-BP Chromatography columns( 4. 6 mm × 250 mm,5 μm) was selected,with the column temperature of 25℃. The contents of five alkaloids in Corydalis Decumbentis Rhizoma were determined simultaneously at a flow rate of 0. 8 mL·min- 1,and the detection wavelength was 280 nm. Result: Under the optimized conditions,baseline separation of five alkaloids was achieved in 20 min,and the resolution is well. The calibration curves of jatrorrhizine,palmatine,berberine,tetrahydropulmatine and protopine were linear in the ranges of 0. 800 9-16. 01,0. 800 9-16. 01,0. 200 2-4. 004,8. 013-160. 3 and 12. 09-240. 7 mg ·L- 1,respectively,with correlation coefficients of 0. 999 5. Their limits of detection( LOD,S /N = 3) were 0. 201,0. 254,0. 053,1. 27 and 1. 05mg·L- 1,respectively. The spiked recoveries of three compounds ranged from 97.34% to 99. 51%. Conclusion:The method is simple,rapid and accurate,and can be used for the quality control of five alkaloids in Corydalis Decumbentis Rhizoma.