使用HPLC進行中藥濃縮製劑柴胡桂枝湯之成分分析，開發出芍藥中paeoniflorin(芍藥)，桂枝中cinnamic acid(桂皮酸)，黃芩中baicalin(黃芩甙)，baicalein(黃芩苷元)，wogonin(漢黃芩素)及甘草中glycyrrhizin(甘草酸)等六種指標成分之多成分同時定量分析方法。各種抽出之試料通過保持在30℃恆溫之HPLC層析管(Cosmosil 5C 18 -AR，4.6mmψ× 250mm)，移動相採用15%及45% acetonitrile-20 mM sodium 1-hexane sulfonate之混和溶液(各用磷酸調至pH3.5)採用梯度沖提法，以1.0~1.3ml/分之流速沖提。六種指標成分之檢測使用UV檢出器，檢測波長設定0~15分為230nm；15~38分為275nm；38~60分為270nm；60~68分為250nm；最後68~75分為275nm。
本法之回收率，同日間及異日間的變異係數幾乎均在5%以下。這個分離法對於柴胡桂枝湯中六種指標成分是安定且值得信賴之定量法，同時也可應用於各種市售濃縮製劑之分析。

An HPLC method was applied for the simultaneous determination of six marker substances in the Chinese medicinal preparation "Chai-Hu-Kuei-Chih- Tang" (柴胡桂枝場). These substances were paeonitlorin in Paeoniae Radix (芍葉), cinnamic acid in Cinnamomi Ramulus (桂枝), baicalin, baicalein, wogonin in Scutellariae Radix (黃芩)，and glycyrrhizin in Glycyrrhizae Radix (甘草).
Extracted samples were run through the HPLC column (Cosmosil 5 Cl18 "AR, 4.6 mm Φ× 250 mm) at 30 ℃ and the column was developed with a mixture of 15% acetonitrile－20 mM sodium 1-hexane sulfonate (pH 3.5) and 45% acetonitrile－20 mM sodium 1-hexane sulfonate (pH 3.5) aqueous solution employing linear gradient elution method at a flow-rate of 1.0-1.3 ml/min. An UV detector was used for the detection of the marker substances. The detection wavelength varied with time. It was 230 nm during 0~15 min, 275 nm during 15~38 min, 270 nm during 38~60 min, 250 nm during 60~68 min, and lastly 275 nm during 68~75 mm.
Relative standard deviations of intra- and inter-day analysis were less than 5%. This separation method could be successfully applied for the simultaneous determination of six marker substances in "Chai-Hu-Kuei-Chih- Tang" (柴胡桂枝湯).