Objective: To establish a high performance capillary electrophoresis method with diode array detection (HPCE-DAD) for simultaneous determination of rutin, isoquercitrin, hyperoside, quercitrin, kaempferol and quercetin in Hyperici Japonici Herba.
Method: Based on the mode of capillary zone electrophoresis, 40 mmol x L(-1) borax was used as buffer solution (pH 8.62), uncoated fused silica capillary (56 cm x 64.5 cm x 75 microm) was used, separation voltage was 25 kV, detection wavelength was at 206 nm, column temperature was maintained at 25 degrees C, and sample was injected at 50 mbar, 8 s.
Result: Six flavonoids showed good linearity (r > 0.9953) in the range of the tested concentration, the average recoveries of the method were between 98.8%-102.9%.
Conclusion: The method is simple, accurate and reproducible, and can be used for quality control of Hyperici Japonici Herba.