“菠菜叶中色素的提取与分离”实验改进

Improving the Experiment of Extraction and Separation of Pigments from a Spinach Leaf

“菠菜叶中色素的提取和分离”是大学有机化学实验课程的重要项目之一,但在教学中一直存在大量使用管制试剂、实验时间过长、实验步骤繁琐、分离效果不佳等问题。本文对菠菜叶色素分离的薄层色谱条件进行了系统探究,尝试采用了正己烷-无水乙醇、正己烷-正丁醇等多种试剂组合作为展开剂,实验结果表明最佳的展开剂是体积比为10.0:1.0的正己烷-无水乙醇。采用正己烷-无水乙醇、正己烷-正丁醇作为洗脱剂进行柱色谱分离实验,最终分别得到了以硅胶为固定相、正己烷-无水乙醇为洗脱剂的梯度洗脱方案以及以中性氧化铝为固定相、正己烷-正丁醇为洗脱剂的梯度洗脱方案。该实验方案使用更友好的试剂,试剂用量少,实验耗时短,分离效果好。

Extraction and separation of pigments from spinach leaf is an important experiment in organic chemistry laboratory,conducted at universities.However,in experimental teaching,there have always been problems,such as the use of toxic or controlled reagents,long experiment time,cumbersome experimental steps,and poor experimental results.In this study,the conditions of thin layer chromatography were systematically explored.A variety of reagent combinations,such as n-hexane/anhydrous ethanol and n-hexane/n-butanol,were tested.It was found that the developing agent with the best separation effect was n-hexane/anhydrous ethanol solution,with a volume ratio of 10:1.The n-hexane/absolute ethanol and n-hexane/n-butanol were also used as eluents to explore column chromatography separation experiments of the pigments from spinach leaf.By using silica gel as the stationary phase,the optimal gradient elution scheme with n-hexane/absolute ethanol as eluent was obtained;whereas,the optimal gradient elution scheme with n-hexane/n-butanol as the eluent was obtained by using neutral alumina as the stationary phase.Following the improvement,the separation effect was enhanced and the amount of reagent was reduced;furthermore,more friendly reagents were used and the teaching time was shortened.