Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Boston University chemists probe secrets in ancient textile dyes from China, Peru

01.04.2005


Chemists journey to Gobi region for samples, discover novel dye in textiles from Peru

Although searching for 3,000-year-old mummy textiles in tombs under the blazing sun of a western Chinese desert may seem more Indiana Jones than analytical chemist, two Boston University researchers recently did just that. Traveling along the ancient Silk Road in Xinjiang Province on their quest, they found the ancient fabrics – and hit upon a research adventure that combined chemistry, archaeology, anthropology, botany, and art.

The chemists, Richard Laursen, a professor in the Boston University Department of Chemistry, and Xian Zhang, a chemistry graduate student, have refined a technique that helps archaeologists and anthropologists identify the plant species that ancient people used to make fabric dyes. Their technique has not only provided researchers with a new, more powerful tool for analyzing previously known dye types, it also has led to the discovery of at least one never-before described dye. In addition, the BU chemists have started a catalogue of plant sample characteristics for use by dye researchers around the world.



Historically, researchers have used a hydrochloric acid mixture to extract the delicate dyes from fabrics such as wool and silk. But, according to Laursen, hydrochloric acid cleaves glycosidic linkages, the bonds that hold sugar-like molecules to many dye molecules. Without these sugars, researchers lose valuable clues to which plants were used to give the dyes their color.

Keeping these clues intact is especially important when analyzing yellow, flavonoid dyes, not only because such dyes are chemically more delicate than red or blue dyes, but also because they can be derived from a greater variety of different plant sources -- from onion skins to pagoda tree buds.

Laursen and Zhang tested dye extraction methods using both ethylenediaminetetraacetic acid (EDTA) and formic acid instead of hydrochloric acid. These "gentler" extraction solutions leave the glycosidic linkages in place. The chemists analyzed the dye extracts using a combination of high-performance liquid chromatography, mass spectrometry, and a diode array detector to determine their solubility properties, molecular weight, and exact color absorption in nanometers.

The researchers have already put their new method to the test, even discovering a new type of dye component, a flavonoid sulfate, in textiles found with 1,000-year-old mummies in Peru.

"Nobody could have seen the flavonoid sulfate with the old method," says Laursen. "Every time we analyze something we find something new. It’s really kind of exciting."

On a recent trip to China, Laursen and Zhang obtained textile samples from yet another mummy. The chemists were attending a Getty Conservation Institute-sponsored conference at Dunhuang, a town at the edge of the Gobi Desert. A site near the town is honeycombed with caves containing ancient Buddhist art. While at the conference, the BU chemists joined an expedition into the Takla Makan (the name means, "You go in, but you don’t come out.") desert. Chinese researchers found the fabric at a Takla Makan burial site, and Zhang, a native of China, convinced a Chinese archaeologist to give her tiny samples of the 3,000-year-old cloth.

According to Laursen, the fabric, and the person entombed with it, are of Indo-European origin, probably linked to ancient migrations west through Central Asia. He plans a trip this spring to collect plants from Central Asia and nearby countries like Turkey, Iran, and Uzbekistan for a chemical comparison with the fabric’s dye to find out more about the mummy’s origin.

"The people in the area have a long tradition of making carpets and textiles," says Laursen, "there is very little known about what plants were used to dye them. We hope to fill this void by collecting as much plant material as we can."

The plant samples he collects will join hundreds of others in a dye "fingerprint" database that the BU scientists are creating for use by researchers around the globe.

"You get a characteristic spectrum of dye components," Laursen explains. "If we had this library, maybe we could figure out what was used in our Chinese samples. That type of information would be of use to archaeologists and anthropologists who are trying to figure out migration patterns and technologies of ancient people."

Ann Marie Menting | EurekAlert!
Further information:
http://www.bu.edu

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>