Objective: To develop a new method for determination of palmatine hydrochloride

dehydrocorydaline nitrate and tetrahydropalmatine in Rhizoma Corydalis by HPLC. Method: The HPLC was adopted performing on a C18column(4.6 mm×250 nm

5 μm) with a mobile phase of acetonitrile(A)-0.1%phosphoric acid(B). The gradient elution program was as follows: 0-20 min

25%A;20-30 min

25%-55%A;30-45 min

55%A;45-50 min

55%-25%A;50-55 min

25%A; The detection wavelength was set at 270 nm and 280 nm. The column temperature was at 30℃. Result: Palmatine hydrochloride was linear in the range of 2.12×10-2-1.59 μg(r=0.999 9); dehydrocorydaline nitrate was linear in the range of 4.10×10-2-3.07 μg(r=0.9999);tetrahydropalmatine was linear in the range of 2.10×10-2-1.57 μg(r=0.9999). The average recovery was 100.10%

100.03% and 97.47%. Conclusion: The method was accurate and had satisfactory efficacy; it can determine palmatine hydrochloride

dehydrocorydaline nitrate and tetrahydropalmatine in Rhizoma Corydalis.