表面增强拉曼光谱对纺织品文物中茜素和茜紫素的快速检测

Rapidly detection of alizarin and purpurin in textile relics by surface-enhanced Raman spectroscopy

为快速检测古代纺织品文物中的天然色素并达到无损分析的目的,采用表面增强拉曼光谱技术(SERS)对纺织品文物中天然染料茜素和茜紫素进行鉴定。以纳米银溶胶为SERS基底检测茜素和茜紫素的标准品,利用密度泛函理论计算结果对茜素和茜紫素分子的SERS光谱进行确认,分析得到茜素和茜紫素的SERS光谱在3种激发波长下的差异,并找出判断茜素和茜紫素存在的特征峰。在此基础上,从纺织品文物中提取1根长度约为2 mm的纤维,采用原位非萃取水解方法对其进行预处理,并进行SERS检测。结果表明,出土于新疆营盘的纺织品文物中红色染料成分是茜素和茜紫素。

In order to quickly detect natural pigments in ancient relics and achieve non-destructive analysis, surface-enhanced Raman spectroscopy(SERS) was adopted to rapidly identify natural dyes of alizarin and purpurin in textile relic samples. Silver colliod was adopted a substrate to detect alizarin and purpurin standard. The SERS spectra of alizarin and purpurin were identified detailed by the density functional theory. The difference of SERS spectra of alizarin and purpurin at three excitation wavelengths was analyzed, and the characteristic peaks for judging the presence of alizarin and purpurin were found. Based on the SERS of alizarin and purpurin standard, extracting a fiber about 2 mm long in the textile relics. After pretreatment of cultural fiber by in situ non-extraction hydrolysis method, SERS technology was used for the detection. The results shows that the red dye components in the textile relics which are unearthed in Xinjiang′s Yingpan plate are alizarin and purpurin.