[Determination of chlorogenic acid and baicalin in Yinhuang film-coated tablets by HPLC isocratic elution].

OBJECTIVE: To establish an HPLC method for determination of chlorogenic acid and baicalin in Yinhuang film-coated tablets. METHOD: HPLC isocratic elution was adopted, with the C18 column (4.6 mm x 250 mm, 5 microm) as the chromatographic column, methanol-water-phosphoric acid (45: 55: 0.2) as the mobile phase. The flow rate was set at 1.0 mL x min(-1), and column temperature was set at 30 degrees C. The detection wavelength was 328 nm, and the sample size was 20 microL. RESULT: At concentrations ranging between 2.200-44.00, 24.20-242.0 mg x L(-1), peak area of chlorogenic acid and baicalin showed good linear relationship, the average recoveries were 99.63% (RSD 1.8%, n = 9) and 99.72% (RSD 1.9%, n = 9), respectively. CONCLUSION: The method is simple that it can accurately measure the content of chlorogenic acid and baicalin in Yinhuang film-coated tablets.