Silk dating to know when garments are
2011/12/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria
Just as the dating of fossils gives information to paleontologists, the dating of garments gives information to historians. However, there is a difference between the two: there are reliable fossil dating techniques, such as carbon 14 isotope based, but until now there was no reliable tissue dating technique without using very high amounts. Now, a chemist from the Smithsonian Museum Conservation Institute in Maryland has improved an old technique for dating small silk samples. This allows you to date museum garments without just damaging the piece.
It is basically a technique similar to that used in fossil dating, but instead of measuring the disintegration of an isotope, it measures a variation of the amino acids of silk proteins. All natural amino acids have the same asymmetric atomic distribution, called isomer L, but over time some amino acids change. Maryland chemists have measured the speed at which this process occurs to calibrate over time this degradation of silk. With this data, the microscopic sample of a garment is sufficient to date with an accuracy of 50-100 years.
This work is not only of interest to historians, but also to biologists for possible applications of natural silk. For example, for its application in medicine, it is important to know how and at what speed silk degrades.
