Determination of scutellarin, baicalein, luteolin and apigenin in Herba Scutellariae barbatae by HPLC

To establish HPLC methods for simultaneous determination of scutellarin, baicalein, luteolin and apigenin in Herba Scutellariae barbatae.The chromatographic conditions were as follows-A Diamonsil-C18 (250 mm × 4.6 mm, 5 μm) was choosed as the chromatographic column, the mobile phase was the mixture of acetonitril (A) and 1% glacial acetic acid in water (B) with gradient elution, the detection wavelength at 335 nm, the flow velocity of 1.0 mL/min, the column temperature at 30 ℃.The linear relationship between content and peak area was obtained during the range of 2.0~200 μg/mL for scutellarin, 0.5~50 μg/mL for baicalein, 0.5~50 μg/m L for luteolin and 0.5~50 μg/m L for apigenin.RSD's founds of the peak area of scutellarin, baicalein, luteolin and apigenin for the precision test, the stability test and the repeatability test were less than 2.0%. The recoveries, average recovery and RSDs of scutellarin, baicalein, luteolin and apigenin obtained were 97.73% ~ 101.7%, 99.72%, 1.36% (n = 9) , 97.78% ~102.8%, 99.53%, 1.99% (n = 9) , 97.40% ~ 102.4%, 99.39%, 1.84% (n = 9) and 97.80% ~ 102.0%, 99.24%, 1.49% (n = 9) .By using the established HPLC methods, 12 samples of Herba Scutellariae barbate in different districts were analyzed.The results showed that the contents of scutellarin, baicalein, luteolin and apigenin were 2.41~7.08, 0.26 ~0.56, 0.31~ 0.90 mg/g and 0.28 ~ 0.95 mg/g, respectively. The method could be applied to simultaneous quantitative assay of scutellarin, baicalein, luteolin and apigenin in Herba Scutellariae barbatae with good specificity, reproducibility and stability.The sampling recovery test is in compliance with the requirement.