薄层分离-分光光度法测定夹竹桃枝中三萜类化合物的质量分数

Quantitative analysis of triterpenoids from the bark of Nerium oleander L by thin layer chromatography-spectrophotometry

为测定夹竹桃中总三萜的质量分数,以齐墩果酸为对照品,5%的香草醛-冰醋酸溶液和高氯酸为显色剂,采用薄层色谱分离-分光光度法在550 nm波长处测定样品吸光度.用正交试验法优化了显色反应条件,适宜的展开剂组成为氯仿∶丙酮=10∶3,对照品在10～200μL/mL范围呈良好线性关系,其回归方程为Y=0.0070C+0.0317,r=0.998 6.夹竹桃中总三萜的质量分数为1.01%.该方法适合夹竹桃中总三萜的质量分数测定,操作简单,灵敏度高且比较准确.

Objective to determination the triterpenoids content in the bark of Nerium oleander L. Under the experimental conditions including oleanolie acid as the reference. 5% vanillin-acetie acid and perehloric acid as color developers, the content of triterp-enoids in Nerium oleander L was determined by the thin laver ehromatographv-spectrophotometric method at 550 nm. The condition was optimized by orthogonal design. The results showed that chloroform： acetone=10 ： 3 as developer, the calibration curve was linear（ r=0. 9986 ）in the range of 20-200 tx L/mL, and the regression equation was Y= 0. 007 0C ＋ 0. 031 7. The content of triterpenoids in the bark of Nerium oleander L was about 1.01%. The spectrophotometry is suitable for the determination of total triterpenoids from Nerium oleander L. This method is convenient, stable and reproducible.