气相色谱法测定合成产物中诺蒎酸的含量

GC Determination of Nopinic Acid in the Products of Its Synthesis

采用气相色谱法跟踪测定了β-蒎烯氧化反应中主产物诺蒎酸的含量;试验结果表明,在SE-30/Chromosorb W/AW(0.25～0.175 mm)的色谱柱上,诺蒎酸与副产物之间具有较好的分离效果,并且在峰形对称性和出峰时间上,SE-30柱也具有优势;该方法的线性范围在15.0～60.0g·L^(-1)之间,检出限(S/N=3)为3.5 g·L^(-1);对同一试样的5次平行测定的相对标准偏差为1.8%;该方法的标准加入回收率达90%～98%。

Nopinic acid was synthesized from β-pinene by oxidation with KMnO4 in alkaline solution, and amount of nopinic acid in the reaction products was determined by gas chromatograph with the SE-30/chromosorb W/AW separation column （0. 25-0. 175 mm）. By use of the proposed column, nopinic acid was nicely separated from the by-products, and well-difined symmetrically shaped peak of nopinic acid was obtained. Linear relationship between peak area and mass concentration of nopinic acid was obtained in the range from 15. 0 to 60. 0 g · L^-1 , with detection limit （S/N=3） of 3. 5 g · L^-1. Recovery and precision of the method were tested, giving value of RSD （n=5） of 1.8% and values of recovery in the range of 90%-98%.