A researcher at the Hebrew University has developed a spray to detect the homemade explosive urea nitrate. The strength of an explosive is 70 percent that of TNT, and due to its similarity to sugar it is difficult to detect
A researcher at the Hebrew University developed a method to identify terrorists who prepared or transported explosives. Prof. Yosef Almog from the Kazali Institute of Applied Chemistry at the Hebrew University has developed a new chemical spray that can detect the chemical urea nitrate, a powerful homemade explosive. When the substance is sprayed on cotton swabs taken from the hands of a suspect in contact with an explosive, a blood-red chemical reaction is produced.
In a conversation with the Hidan website, Prof. Almog says that the strength of the improvised explosive is about 70 percent of the standard military explosive - TNT. The means of detecting the explosive substance, which he developed together with research student Nathai Lamberger, is cheap to use and easy for anyone to learn without the need for prior training in chemistry, including police officers and security guards at border crossings.
Urea nitrate is a colorless crystalline substance that resembles sugar, making it very difficult to identify by appearance alone. Development of this type of color test will significantly assist forensic scientists. The test is based on the formation of a red color in the chemical reaction between the chemical reagent p-dimethylaminocinnamaldehyde and urea nitrate.
This study, by research student Nathai Lamberger under the guidance of Prof. Almog, was published in the September issue of the Journal of Forensic Sciences. This is a continuation of the research done two years ago with the support of the American-Israeli Binational Committee to War on Terrorism.
"Unlike some other home-made explosives, whose first discovery was in Israel, this substance was discovered in illegal use even before us in the USA, in the late 93s. It was used criminally as an explosive device, and among other things was used for the first explosion in the Twin Towers in February XNUMX, where the terrorists used half a ton of this material," says Prof. Almog in an interview.
What is special about urea nitrate?"This material is problematic for the defender. First - it is so easy to prepare, at such a low price. Second, it is difficult to distinguish it from completely innocent substances by sight. It is odorless, it looks really like sugar. A new method was therefore required. Also in terms of its chemical properties it is different from most other explosives and therefore it was a problem that needed to be dealt with. There are already devices on the market that are supposed to detect urea nitrate, but they are still in the experimental stages due to their complexity and high price."
According to Prof. Almog, "the spray we developed can detect even tiny traces of improvised explosive material found in the hands of suspects, on handles, on storage devices and vehicles. The spray can distinguish between sugar, or any other innocent powder, and urea nitrate."
How did you arrive at the substance that detects the substance that detects the explosive?"The research was divided into three phases. In the first step, we developed the dye preparation and showed that it is sensitive and specific, and checked that it only reacts with this substance. In the second step, we examined the exact structure of the dyed material - what gives the color, why it is obtained. In the third step, which should be published later, we will try to identify the material also in the remains after an explosion."
How can an ordinary person be warned about the explosive?"It is no different in this respect from other explosives, the danger of which is always hovering. The device is not for use by citizens, but by law enforcement authorities - military, security, inspectors at crossing points, etc. But if a citizen suspects that he sees a substance that is not where he expects it and looks like sugar, he should report it."
Prof. Almog points out that this is a material that Palestinian terrorists often use. Amateur chemists can prepare a large amount of this substance at home and use it in improvised mines and suicide bombers' explosive belts. Explosives of this type have already killed hundreds of Israelis.
According to Prof. Almog, the topic of detecting explosives is only a small part of the institute's activities. "At the Kazali Institute, we deal with applied chemistry, mainly for the benefit of industry: improving production processes, materials that can replace living tissues, nanochemistry, using new technologies from the nanofield to replace existing methods. We also deal with green chemistry - a topic that has gained momentum recently, and are looking at how to help the chemical industry produce less toxic substances. And of course forensic chemistry - using chemical methods to solve crimes and obtain solid evidence."
