Simultaneous determination of baicalin, wogonoside, baicalein, wogonin, and oroxylin-A in Scutellaria baicalensis by UPLC

Objective To establish a UPLC method for the simultaneous determination of five constituents(baicalin, wogonoside, baicalein, wogonin, and oroxylin-A) in Scutellaria baicalensis. Methods Five constituents in S. baicalensis were simultaneously determined by UPLC with Waters Acquity UPLC BEH C18 column(50 mm × 2.1 mm, 1.7 μm). With a gradient program of acetonitrile-0.1% formic acid at the flow rate of 0.6 mL/min, and the detection wavelength was set at 280 nm. Results Baicalin, wogonoside, baicalein, wogonin, and oroxylin-A in S. baicalensis were clearly and respectively separated in 15 min. The relationship between the concentration and the peak areas of the five constituents in S. baicalensis was all linear. The RSD of recovery, precision, and reproducibility was all less than 3.0%. Conclusion The method is rapid, simple, reliable, and accurate, and has been successfully used to the quantification of the five constituents in S. baicalensis.