New material lights up on detecting explosives

Scientists have created a new material which turns fluorescent on detecting molecules of explosives, an advance that may help improve security measures.
The new material consists of a set of molecules TTF-C[4]P and TNDCF, which react when encountering explosives in their vicinity.
TNDCF becomes fluorescent when an explosives molecule is introduced to the set of molecules.
"This new knowledge could lead to creating a small device based on this set of molecules. With such a device security staff in airports could test if there are explosive molecules on or near a bag," said first author Steffen Bahring, from University of Southern Denmark.

This is not the first time scientists report the development of chemical substances capable of detecting explosives.
However, previously many uncertainties have been involved, and therefore the methods have not been entirely reliable.

One problem is that previous techniques have been based on a substance that became fluorescent when there were no explosives molecules in the vicinity and that the fluorescence disappeared if the substance came into contact with explosive molecules.
"The problem was that several factors could make the fluorescence disappear; a number of salts for example had this effect. Thus these substances could give off a false alarm," said Bahring.

The new material only turns fluorescent when exposed to molecules from the explosive TNB and some specific salts, such as those based on chlorine or fluorine.
"There can only be two reasons why it turns fluorescent, one of them being the presence of explosives. Thus this material is a highly reliable tool for detecting explosives," said Bahring.
The research was published in the journal Chemistry.