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

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.