"The potential uses of smell technology are endless," notes Josep Samitier, the coordinator of the SPOT-NOSED project that developed nanobiosensors to mimic the way human and animal noses respond to different odours.
This new nose biosensor is unusual in how it's made. By placing a layer of proteins that constitute the olfactory receptors in animal noses on a microelectrode and measuring the reaction when the proteins come into contact with different odorants, the system is capable of detecting odorants at concentrations that would be imperceptible to humans.
"Our tests showed that the nanobiosensors will react to a few molecules of odorant with a very high degree of accuracy. Some of the results of the trials surpassed even our expectations," Samitier says. These tiny bioelectronic sensors, he says, represent a 'major leap forward' in smell technology and a clear example of a biomimetic devices obtained by converging Nano-Bio-Info technologies.
Several hundred different proteins, which the SPOT-NOSED researchers genetically copied from rats and grew in yeast, would be needed for an electronic nose to detect almost any smell because different proteins react to different odorants and it is the resultant combination of reactions that identifies a certain smell. Nanotechnology makes such an electronic nose feasible, the coordinator notes, even though the human nose uses 1,000 different proteins to allow the brain to recognise 10,000 different smells.