A fly’s sense of smell could be used in new technology to detect drugs and bombs, according to research.
Brain scientist Professor Thomas Nowotny, who works at the University of Sussex, was surprised to find that the “nose” of a fruit fly can identify odours from illicit drugs and explosive substances almost as accurately as the smell from wine.
The insects are naturally attracted to wine because it smells like their favourite food, fermenting fruit, he said.
The study, published in the journal Bioinspiration and Biomimetics, brings scientists closer to developing electronic noses that closely replicate the sensitive olfactory sense of animals.
The hope is that e-noses will be more sensitive and faster than commercially available products which are typically based on metal-oxide sensors and are very slow compared with a biological nose, the university said.
Nowotny, who specialises in informatics, led the study with researchers from Monash University and the Commonwealth Scientific and Industrial Research Organisation in Australia.
He said: “Dogs can smell drugs and people have trained bees to detect explosives.
“Here we are looking more for what it is in the nose – which receptors – that allows animals to do this.
“In looking at fruit flies we have found that contrary to our expectation, unfamiliar odours, such as from explosives, were not only recognised but broadly recognised with the same accuracy as odours more relevant to a fly’s behaviour.”
The ‘nose’ of a fruit fly can identify odours from illicit drugs and explosive substances almost as accurately as the smell from wine
Nowotny and his collaborators recorded how 20 different receptor neurons in fruit flies responded to an ecologically relevant set of 36 chemicals related to wine (the wine set) and an ecologically irrelevant set of 35 chemicals related to hazardous materials, such as those found in drugs, combustion products and the headspace of explosives (the industrial set).
By monitoring the “firing rate” of each neuron, they were able to assess which smells elicited the strongest reactions from the flies.
The team used a computer programme to simulate the part of the fly’s brain used for recognition to show that the receptor responses contained enough information to recognise odours.
Of the wine set, 29 out of the 36 compounds elicited clear excitatory responses in at least one receptor neuron, the study showed.
But Nowotny’s team was surprised to find that the flies also responded to 21 out of the 35 substances related to drugs and explosives. He said: “The long-term goal of this research direction is to recreate animals’ noses for technical applications.”