Identification of Natural Dyes in Selected Museum Textiles Using High Performance Liquid Chromatography with Photodiode Array Detection (HPLC-PDA)

The present study has employed a high performance liquid chromatographic method coupled with a diode array detector (HPLC-DAD) to identify the dyestuffs in textile samples collected from the Coptic Museum in Cairo and the Museum of Jordanian Heritage. The results indicate that mixtures of organic dyes are used in dyeing these samples to produce different colours. The most dominantly identified colourants in samples collected from the Museum of Jordanian Heritage are laccaic acid, kermesic acid, munjistin and indigotin. The most dominantly identified dyestuffs are lac dye (Kerria lacca, Kerr), kermes (Kermes vermilio), madder (Rubia) species and indigoid dye source, either indigo (Indigofera species) or woad (Isatis tinctoria L.). These results confirm the historical information in the Museum of Jordanian Heritage in that the tested textile objects date back to the end of the 19^th century or the beginning of the 20^th century. The most dominantly identified colourants in samples collected from the Coptic Museum are alizarin, purpurin, and indigotin. The most dominantly identified dyestuffs are madder and indigotin. Based on this investigation, it is concluded that the tested dyed samples collected from the Coptic Museum belong to the 6-7^th centuries. This conclusion is in agreement with the initial dating of samples according to the style of the decorations.