Investigation of Natural Dyes and Taxonomic Identification of Fibers Used in Chancay Textiles by Vibrational Spectroscopy and Mass Spectrometry.

Abstract

Textiles provide a valuable source of information regarding past cultures and their artistic practices. Understanding ancient textiles requires identifying the raw materials used, since the origin of dyes and fibers may be from plants or animals, with the specific species used varying based on geography, trade routes and cultural significance. A selection of nine Chancay textile fragments attributed to 800-1200 CE were studied with liquid chromatography mass spectrometry (LC-MS) and direct analysis in real time mass spectrometry (DART-MS) to identify the chemical compounds in extracts of natural dyes used to create green, blue, red, yellow and black colors. From the identified molecular markers, the green colors involved the overdyeing of indigo and flavonoid dyes, the blue colors were achieved using an indigo dye, the yellows came from a flavonoid dye, the reds from anthraquinone dyes of both plant and animal origin, and the black from a mixture of flavonoid, anthraquinone and indigo dyes. A subset of the textiles was identified as containing proteinaceous fibers based on ATR-FTIR. These textiles were further studied using a mass spectrometry-based proteomics approach to identify the species used, with the peptide sequences measured confirming the presence of South American camelids, most likely llama or alpaca.