HPLC Simultaneous Determination of Chlorogenic Acid and Baicalin in Shuanghuanglian Preparations

HPLC was applied to the simultaneous determination of chlorogenic acid and baicalin in “Shuanghuanglian” compound preparations.Waters Symmetry C18 column (3.9 mm×150 mm,5 μm) was used in the chromatographic separation,and a solution containing methanol and dilute.phosphoric acid was used as the mobile phase in the gradient elution,with a flow-rate of 0.8 mL·min-1.UV-detection at 320 nm was selected in the determination.Linearity range for determination of chlorogenic acid was found in the range of 1.72-137.6 mg·L-1 (y=28 900.12+23 036.71 x,r=0.999 6),and for determination of baicalin in the range of 3.35-267.9 mg·L-1 (y=19 940.40+13 564.15 x,r=0.999 8).The RSD′s found in the precision test were 3.53% (n=7) for chlorogenic acid,and 2.85% (n=7) for baicalin,and average recovery obtained were 95.8% and 97.3% respectively.