西藏紫草色素的萃取与吸光度分析

Dye Extraction and Absorbance Analysis for Tibetan Lithospermum

通过采集西藏本地紫草,萃取了西藏紫草的根部色素。分析显示拉萨紫草根部皮层最多可达15层。利用索氏提取法提取了5种紫草色素,通过色谱柱分离出16种纯色素。利用紫外-可见分光光度计测量了3种紫草色素的吸光度。实验结果表明,紫草色素对紫外线(300～400nm)具有良好的吸收作用;紫草根部外层皮色素含量比里层的丰富;使用三氯甲烷萃取剂提取的外皮层色素在可见光区具有较高的吸光度。因此,紫草根部外皮层的色素在理论上可以用来当做研制染料敏化太阳能电池的光敏剂。

We collect the Tibetan local lithospermums,and extract the root pigments of lithospermum.The analysis shows that the maximum number of the root cortexes for Lhasa local lithospermum reach up to fifteen.The work extracts five different pigments by using Soxhlet extraction method,and separates 16 kinds of pure pigments by using column chromatography method.Measuring absorbance for three lithospermum pigments through using UV-visible spectrophotometer. The experimental results show that the majority of lithospermum pigments have good absorption properties for UV radiation（300nm-500nm）,the outer layers of the lithospermum roots content richer pigments than the inner layers.The outer cortex dyes extracted through using chloroform extraction have a higher absorbance in the visible region.Therefore, lithospermum pigments,in particular,pigments from the outer layers of the lithospermum roots could be used as a photosensitizer to the development of dye-sensitized solar cells.