What does an electronic nose smell?

These innovative systems serve both to detect diseases through olfactory patterns and to find and deactivate explosive devices

  When it comes to competing in the animal kingdom, the human nose loses the battle at the first moment of change. According to a study by Japanese researchers, elephants have a smell five times more developed than that of humans and more than dogs. They have 811 olfactory receptors. Humans only 386, although for some scientists there is no problem.

"We can detect and discriminate an extraordinary range of smells, we are more sensitive than rodents and dogs to some of them, we are able to track odor traces and our behavioral and affective states are influenced by our sense of smell," says John McGann , associate professor at Rutgers University in New Brunswick.

    Although the best friends of the human being, dogs, are still the preferred ones to detect explosives and prohibited substances, the advance of technology has introduced a new protagonist in this sector: the electronic naris. "A person or an animal is able to distinguish according to what smell due to sensors that connect with the neurons of the brain." An "eNose", in a certain way, does the same, "says Juan Bautista Talens, a professor at the Polytechnic University of Valencia (UPV).

Bautista is part of the group of researchers at the Gandía campus of the UPV and the La Fe Sanitary Research Institute (IIS La Fe) that has developed a prototype electronic nose that can distinguish patients with Crohn's disease and ulcerative colitis. More than 400 tests conducted since 2014, all based on a simple 'software' and 32 sensors. "Through the use of 'software' for data mining, we can test with different algorithms and / or neural networks reserving samples to test them and samples to train," says Bautista. This system is able to recognize olfactory patterns, so they are trying to test those substances that may have differences in their aroma. "Stools in the case of digestive diseases and urine in other pathologies",

     The device - called Moosy 32 eNose - also detects if the disease is active with an accuracy close to 90%. The nose devised by the Valencian researchers can detect volatile organic compounds that act as diagnostic markers or of intensity of the activity of the disease. "Although it may seem simple, it requires a lot of analysis, repetitions, adjustments and simulations." 

Pilar Nos, Head of Digestive Medicine at Hospital La Fe, explains that "volatile organic compounds are originated by physiological processes of metabolism in the human body, and are expelled as waste through faeces. being a differential marker in certain intestinal diseases and its precise detection, through non-invasive devices such as the electronic nose, would be a great advance for the diagnosis and monitoring of the evolution of these diseases. "

The development of this prototype has been funded by the Generalitat Valenciana. In addition, the initial part of the project - the feasibility study that served to establish the foundations of the system - was paid for by Inbio, a scientific collaboration structure between the UPV and La Fe. Although "funding has been terminated", denounce Baptist.

'ENose' cops
The technological advance in this sector is not only focused on medicine. Two researchers from the Group of Perception and Intelligent Systems (PSI) of the University of Extremadura together with the chief inspector of the TEDAX-NRBQ Group of Badajoz have developed the research work "Artificial Olfactory Systems for the Detection of Hazardous Agents".

A laborious project whose authors, Jesús Lozano Rogado and José Luis Herrero and policeman José Miguel Sánchez, have been awarded the Spanish Police Foundation Research Prize for 2016-2017. Its proposal of artificial olfactory system allows to detect chemical and explosive atmospheres remotely by means of gas sensors, combined with artificial intelligence techniques . The device, which is easy to use through a mobile phone or tablet, has as its main advantage the security it offers TEDAX specialists to be able to work remotely.

"It is an electronic system that incorporates several sensors of gases, temperature and humidity that are connected wirelessly to a device that performs data processing and indicates what type of environment the device is in," Jesús Lozano explains in an interview. release.

Current threats require a very wide field in the search for new detection technologies that are translated at the field level in equipment with high response speed, sensitivity, small size, low cost, low frequency of false alarms, etc., for improve the response to these NRBC-E attacks, in which the price does not represent a stumbling block to guarantee security.

'Low cost' system
"This electronic system, compared to other technologies on the market, has the added value of its low cost, since with only 700 euros you have similar benefits than other much more expensive detectors," says the University of Extremadura on its website.

In addition, the main advantage offered by this device is the possibility of working remotely. For the TEDAX work of the Police , one of the key requirements is security, so this point becomes vital. The electronic nose can be adapted to a drone or mobile robot avoiding personal travel to the dangerous area. In addition, you can consult the data in real time.

Laboratory tests support this system for the detection of explosives, dynamite, gunpowder, pentrite and chemical substances such as chlorine, ammonia, acetone and hydrogen peroxide. It can also detect the precursors of the TATP explosive, commonly used by jihadist terrorism. Until now, there was no detector that contemplated such a diverse range of explosives and narcotics.