Simultaneous Determination of Liquiritin, Isoliquiritin, Glycyrrhizin, Isoliquiritigenin and Glycyrrhizic Acid in Licorice Extract by HPLC Dual Wavelength Spectrophotometry / 中国中医药信息杂志

ABSTRACT

Objective To establish a method for the simultaneous determination of liquiritin, isoliquiritin, glycyrrhizin, isoliquiritigenin and glycyrrhizic acid in licorice extract. Methods Liquiritin, isoliquiritin, glycyrrhizin, isoliquiritigenin and glycyrrhizic acid in licorice extract were determined by HPLC dual wavelength spectrophotometry. Symmetry C18 column (4.6 mm × 250 mm, 5 μm) was used. The mobile phase was acetonitrile (A) - 0.085％ phosphoric acid water (B), ingradient elution mode (0–8 min, 81％ B; 8–35 min, 81％→50％ B; 35–60 min, 50％ B) with the flow rate of 1.0 mL/min. The sample size was 10 μL, and column temperature was room temperature. Dual wavelength detection, λ1=237 nm, λ2=254 nm. Results Liquiritin, isoliquiritin, glycyrrhizin, isoliquiritigenin and glycyrrhizic acid were linear in the ranges of 0.0408–0.816 μg, 0.0528–1.056 μg, 0.0224–0.448 μg, 0.0212–0.424 μg, and 0.0448–0.896 μg, respectively. The average recovery was 98.69％, 98.31％, 99.10％, 98.55％, and 99.14％, respectively; RSD was 1.39％, 1.29％, 1.78％, 2.14％, and 1.15 ％, respectively. Conclusion The method is accurate, reliable and specific. The results are stable with good repeatability. It can be used for the determine of above 5 components in licorice extract.