Researchers at the University of Oviedo (Spain) have come up with a way of tagging gunpowder which allows its illegal use to be detected even after it has been detonated. Based on the addition of isotopes, the technique can also be used to track and differentiate between wild fish and those from a fish farm, such as trout and salmon.
A new method for tagging and identifying objects, substances and living beings has just been presented in this month's issue of the Analytical Chemistry journal. Its creators are scientists at the University of Oviedo who have patented the procedure for inserting chemical tags into products in a way that allows them to be unmistakably identified over time.
The technique consists of adding two stable (non-radioactive) isotopes (types of the same chemical element but with a different number of neutrons) at an established ratio to the object that is to be followed. Then, with an instrument called a mass spectrometer, a sample can be verified as having the predefined isotope ratio. If it does, it is therefore the tagged product.
"This technology is applicable to the invisible tagging of manufactured substances and objects such as explosives, jewellery, artwork, foods and medicines, which helps to prevent fraud and counterfeiting," explains to SINC Jos Ignacio Garca Alonso, one of its authors. "Through simple analytical techniques, a product can be traced from its origin and any possible illegal uses can be detected," he adds.
The researchers have applied this method to gunpowder, an example of an explosive, by adding two tin isotopes (Sn117 and Sn119). After preparing three different mixes (each with differing isotopic proportions so that they can be distinguished from one another), the results reveal that even after detonation the added tags can still be detected in the explosion remains.
Garca Alonso states that "such a procedure can be used in tagging explosives for civil or mili
FECYT - Spanish Foundation for Science and Technology