Ormylia Art Diagnosis Center, Ormylia 63071, Chalkidiki, Greece.
Anal Bioanal Chem. 2009 Dec;395(7):2175-89. doi: 10.1007/s00216-009-3137-6. Epub 2009 Oct 2.
Different methods for the extraction of Dactylopius coccus Costa, Rubia tinctorum L., Isatis tinctoria L., Reseda luteola L., Curcuma longa L. and Cotinus coggygria Scop. from wool fibres are investigated using high-performance liquid chromatography with diode array detector (HPLC-DAD). The efficiencies of five extraction methods which include the use of HCl (widely used extraction method), citric acid, oxalic acid, TFA and a combination of HCOOH and EDTA are compared on the basis of the (a) number, (b) relative quantities, measured as HPLC peak areas and (c) signal-to-noise ratios (S/N) of the compounds extracted from the wool substrates. Flavonoid glycosides and curcuminoids contained in R. luteola L. and C. longa L., respectively, according to liquid chromatography with mass spectrometry (LC-MS) identifications, are not detected after treating the fibres with HCl. All the other milder methods are successful in extracting these compounds. Experiments are performed using HPLC-DAD to compare the HPLC peak areas and the S/N of the following extracted compounds: indigotin, indirubin, curcumin, demethoxycurcumin, bisdemethoxycurcumin, fisetin, sulfuretin, luteolin, luteolin-7-O-glucoside, apigenin, carminic acid, alizarin, puruprin and rubiadin. It is shown that the TFA method provides overall the best results as it gives elevated extraction yields except for fisetin, luteolin, apigenin and luteolin-7-O-glucoside and highest S/N except for fisetin and luteolin-7-O-glucoside. It is noteworthy that treatment of the fibres with the typical HCl extraction method results overall in very low S/N. The TFA method is selected for further studies, as follows. First, it is applied on silk dyed samples and compared with the HCl method. The same relative differences of the TFA and HCl methods observed for the wool dyed samples are reported for the silk dyed samples too, except for rubiadin, luteolin and apigenin. Thus, in most cases, the nature of the substrate (wool or silk) appears to have negligible effects on the relative difference of the two extraction methods. Second, the selected TFA method is applied to treat wool and silk historical samples extracted from textiles of the Mamluk period, resulting in the identification of several colouring compounds. In all extraction methods mentioned above, DMSO is used to dissolve the dyes, after acid treatment.
采用高效液相色谱-二极管阵列检测（HPLC-DAD）法，对从羊毛纤维中提取胭脂红蚧、茜草、菘蓝、黄栌、姜黄和黄栌的不同方法进行了研究。基于（a）数量、（b）相对含量（以 HPLC 峰面积表示）和（c）从羊毛基质中提取化合物的信噪比（S/N），比较了 5 种提取方法（包括盐酸法、柠檬酸法、草酸法、TFA 法和甲酸-乙二胺四乙酸（EDTA）组合法）的效率。根据液相色谱-质谱（LC-MS）鉴定，从黄栌和姜黄中提取的类黄酮糖苷和姜黄素，用盐酸处理纤维后均未检出。所有其他温和的方法都能成功提取这些化合物。实验采用 HPLC-DAD 比较了以下提取化合物的 HPLC 峰面积和 S/N：靛蓝、靛玉红、姜黄素、脱甲氧基姜黄素、双脱甲氧基姜黄素、漆黄素、二硫代黄素、木犀草素、木犀草素-7-O-葡萄糖苷、芹菜素、胭脂酸、茜草素、puruprin 和矢车菊素。结果表明，TFA 法除了漆黄素、木犀草素、芹菜素和木犀草素-7-O-葡萄糖苷外，提取产率较高，除了漆黄素和木犀草素-7-O-葡萄糖苷外，S/N 较高，总体效果最好。值得注意的是，用典型的盐酸提取法处理纤维，总体上 S/N 非常低。因此，选择 TFA 法进行进一步研究。首先，将其应用于真丝染色样品，并与盐酸法进行比较。同样的相对差异 TFA 和 HCl 方法观察到的羊毛染色样品也报道了真丝染色样品，除了矢车菊素、木犀草素和芹菜素。因此，在大多数情况下，基质的性质（羊毛或真丝）似乎对两种提取方法的相对差异没有影响。其次，将选定的 TFA 法应用于从马穆鲁克时期纺织品中提取的羊毛和丝绸历史样品进行处理，结果鉴定出几种着色化合物。在上述所有提取方法中，在酸处理后，均使用 DMSO 溶解染料。
