[HPLC determination of four flavonoids in rat plasma after oral ecliptae herba extract].

OBJECTIVE: To establish an HPLC method for determination of four flavonoids in rat plasma after oral Ecliptae Herba extract. METHODS: HPLC separation was carried out in a Neocleodur 100-5 C18 column (250 mm x 4.6 mm, 5 microm) with mobile phase A (consisting of methanol-0.2% phosphoric acid = 50:50) and mobile phase B (acetonitrile)with gradient elution at the flow rate of 1.0 mL/min. The detection wavelength was 350 nm and the column temperature was maintained at 40 degrees C. RESULTS: There were good linear relationships between concentration and peak area ratio of luteolin, apigenin, scutellarein and diosmetin in the ranges of 0.02-50 microg/mL with the recovery rates of 71.5%-90.2%. CONCLUSION: This method is rapid, accurate and reproducible for determination of luteolin, apigenin, scutellarein and diosmetin in rat plasma and study on pharmacokinetics of Ecliptae Herba extract.