柱前衍生化HPLC-UV测定牛膝中齐墩果酸的含量

目的建立牛膝中齐墩果酸的柱前衍生化高效液相色谱测定法。方法以对硝基苯甲酰氯为衍生化试剂,对齐墩果酸分子中的羟基进行苯甲酰化,以乙腈-0.2%磷酸水溶液（95∶5）为流动相,在254nm波长处检测。结果齐墩果酸衍生化产物线性回归方程为：Y=85197X＋22550（r=0.9998）,表明齐墩果酸衍生产物在2.0～6.0μg内线性关系良好。结论所建立的柱前衍生化HPLC-UV可用于牛膝中齐墩果酸的含量测定,齐墩果酸与对硝基苯甲酰氯反应,衍生物为对硝基苯甲酸齐墩果酸酯,紫外检测波长由210nm红移至254nm,与以往方法比较,大幅改善了测定效果,提高了检测灵敏度。该方法准确,灵敏度高,为牛膝药材的质量评价提供了参考依据。

A Pre-Column Derivatization HPLC-UV Method for the Determination of Oleanolic Acid in Achyranthes bidentata Bl.

OBJECTIVE To develope a pre-column derivatization HPLC method for the determination of the content of oleanolic acid in Achyranthes bidentata Bl.METHODS The hydroxyl of oleanolic acid molecules was benzoylated by paranitrobenzoyl chloride as derivatizing reagent.The eluent consisted of acetonitrile-0.2% phosphoric acid solution（95：5）,and the detected wavelength was 254 nm.RESULTS The linear regression equation of derivatives of oleanolic acid was Y=85 197X ＋22 550（r=0.999 8）,the content of derivatives of oleanolic acid showed a good linearity within the concentration range of 2.0-6.0 μg.CONCLUSION The established pre-column derivatization HPLC-UV method can be used for the determination of the content of oleanolic acid.The derivatives is p-nitrobenzoic acid ester-olean,the UV detected wavelength redshifted from 210 nm to 254 nm.The method is accurate,and compared with previous methods,the effect of the determination and the detection sensitivity is greatly improved,which offered a scientific basis for controlling the quality of Achyranthes bidentata Bl.