Single-sample method transforms archaeological textile study
Archaeological textiles hold invaluable information about ancient cultures, trade routes and daily life. However, these precious artefacts are often degraded or charred beyond recognition, making comprehensive analysis extremely challenging. The EU-funded PARCA(opens in new window) research team is revolutionising the study of archaeological textiles. The project developed an innovative methodology to extract maximum information from minimal samples, analysing both dyes and proteins from a single extraction.
One sample, two analyses
During her postdoc, PARCA’s project researcher, Ilaria Serafini, came across a mineralised artefact with gold decorations and charred textiles held by Sapienza University of Rome’s ‘Textiles Culture at Pompeii’ project. “The opportunity to analyse these finds was unique, but I quickly realised there was a lack of methodology that combined the two main pillars of dye analysis and proteomics (the analysis of proteins to determine fibre composition and origin),” explains Serafini. “Considering the preciousness of these artifacts, it was unthinkable to request more than one sample.” PARCA’s solution involves a unique extraction treatment for dyes and proteins in a single step, which can be done using two protocols. The first uses modified urea, a basic environment with chaotropic(opens in new window) and reducing agents. These agents are useful for extracting both keratins(opens in new window) and dyes, with the addition of a chemical that helps release dyes from the textile fibres. The second protocol employs rapid extraction using specialised chemicals at 90 ºC for 10 minutes. This dual approach allows researchers to adapt to different sample conditions. When textiles are well preserved, the urea protocol is among the most effective, while the second is used when there is soil contamination, a common challenge with archaeological finds. The methodology reduces processing time from the usual three or four days down to just one or two, without compromising analytical quality. After the single-step extraction, the samples are analysed using mass spectrometry(opens in new window), a technique that can identify tiny amounts of different molecules. This approach allows researchers to detect a wide range of compounds, including degraded dyes and proteins, offering a detailed view of the materials’ condition.
Opening new windows in archaeological research
Undertaken with the support of the Marie Skłodowska-Curie Actions(opens in new window) programme, PARCA allowed researchers to inspect archaeological finds that had previously generated limited to no results, such as charred remains. Samples from Greece and areas around Mount Vesuvius, particularly Pompeii, have been analysed and the findings are currently being processed. “The data obtained from experiments on charred textiles have demonstrated how the methodology developed overcomes limitations and provides information about the survival of dyes and proteins. This can be a turning point for archaeologists and historians to reconstruct the history of sites,” states Serafini. The project also consolidated broader institutional change. Sapienza University established A3TEX(opens in new window), an interdisciplinary research centre that unites six departments studying textile heritage, fostering cooperation between archaeologists, museologists, historians and other researchers. PARCA’s collaboration with the Smithsonian’s Museum Conservation Institute in the United States has also contributed to setting new standards for cultural heritage research worldwide. “Applied sciences in cultural heritage represent one of the most stimulating analytical fields, precisely because of the complexity of the samples and the impact that such analyses have on artistic and cultural heritage in terms of history, conservation and human legacy,” says Serafini. “PARCA marked the beginning of a new way of working in textile studies, unifying two branches – dye analysis and proteomics – which until now had been travelling on parallel paths.”
