Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Keen Sense Of Smell

31.10.2003


A unique device has been designed by the Moscow scientists – specialists of the Institute of General Physics, Russian Academy of Sciences, supported by funding from the Russian Foundation for Basic Research. The device not only helps to discover in a few seconds the minute quantities of narcotics and explosives in the air, but to identify and even count every single molecule of these dangerous substances. For the first time has the man managed to approach the creation of device more sensitive than the dog’s nose, besides, it is impossible to either divert or frighten or distract the device from trace.



As a matter of fact, all known methods – and there are several of them – either need preliminary division of air samples (that decreases significantly the sensitivity, and increases the duration of analysis and complicates the detection process) or determine the structure of a substance by its fragments. If the structure of a compound is complicated, and if this is not the sole substance in the sample (this is a common case), then instrumental inspection methods fail the fulfil the task. The task is beyond their “sense of smell”. That is why specially trained dogs have to be involved as their sense of smell is several times more sensitive than that of a man (which is natural), and even of that of the most complicated devices. However, here occur other problems: for instance, a handful of pepper completely deprives a four-legged “smeller” of an opportunity to spot the required scent. Besides, the dog, like human beings, may be in low spirits, or may have blocked nose, the dog can be diverted or distracted from trace – the criminal world has invented a lot of means. Therefore, the device is needed – an unbiassed, reliable and at the same time highly sensitive and selective one. The Moscow researchers have managed to develop such a device.

The device is based on a completely new principle developed by the Institute of General Physics (Russian Academy of Sciences) jointly with the University of Montana, USA. The essence of the principle is as follows: molecules of the sought substances first “settle” – they are sorbed on a specially processed silicic surface and interact with it. Then the laser beam, figuratively speaking, knocks the molecules off the surface but in a slightly different form. They have become positive ions, which differ from the original molecules by one thing only – a hydrogen ion (proton) is either added to or removed from them.


Such ions are easy enough to analyze – with the help of the so-called time-of-flight mass-spectrometer. The ions are sped up in the mass-spectrometer, and their mass is determined by the time of flight towards the target – and they are respectively identified.

“I should note we are very lucky, says Sergey Nikiforov, Ph. D. (Physics and Mathematics), project manager. The most widespread narcotics and explosives, and the majority of poisonous substances are nitrogen-containing compounds, possessing one property in common – the ability to participate in the proton exchange reactions (metathesis). Thanks to that, these substances can be analyzed with the help of our method – to be sorbed on silicon and to be protonated (or deprotonated) by the laser beam. There is no complete understanding of the ionization process on the rough surface yet and we are carrying out intense basic research supported by the Russian Foundation for Basic Research. Nevertheless, we have managed to utilize the fact, practically the gift of fortune or nature.”

Preliminary, the developers had to solve two complicated tasks. Firstly, to secure that the majority of the sought molecules “get stuck” to the sorbent – i.e., silicon wafer. To this end, the researchers made the silicon wafer rough, having significantly increased thereby the surface area of silicon.

Seconly, the standard sample was required. It was needed to create extremely low concentrations of the sough substances or their analogues, strictly quantitatively – in minor amounts of molecules. It is impossible to achieve that by simple dilution – this is too inaccurate. The method offered by the developers is exceptionally witty. The researchers have applied a well-known principle – the so-called piezosensitive element. This is a quartz plate, but with a preliminary covering, the weight of which can be measured by the oscillation frequency of the plate. The scientists suggested that the standard sample substance should be introduced into this covering like in the matrix. The substance gets evaporated in the vacuum chamber, and the difference of weight – and accordingly, the quantity of the substance, which got into the bulk of the chamber, - can be precisely measured by the oscillation frequency of this piezoelement.

As a result, the scientists have succeeded not only in developing a fundamentally new method, which allows to detect (as well as dogs do) the explosives and narcotics by minute (track) quantities of their vapor in the air. The researchers have also managed to produce and standardize the first pre-production model of such analyzer. Now they need to optimize its parameters and to develop the software so that the device could operate automatically. According to the inventors, this can be done within a year subject to sufficient funding of the project.

Sergey Komarov | alfa

More articles from Process Engineering:

nachricht Fraunhofer researchers develop measuring system for ZF factory in Saarbrücken
21.11.2017 | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP

nachricht New manufacturing process for SiC power devices opens market to more competition
14.09.2017 | North Carolina State University

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

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,...

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

Corporate coworking as a driver of innovation

22.11.2017 | Business and Finance

PPPL scientists deliver new high-resolution diagnostic to national laser facility

22.11.2017 | Physics and Astronomy

Quantum optics allows us to abandon expensive lasers in spectroscopy

22.11.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>