Massachusetts Institute of Technology (MIT) scientists said Monday they have moved closer to creating "artificial noses," after finding a way to mass-produce smell receptors in a laboratory.
Artificial noses could one day replace dogs that sniff out drugs and explosives, and could have numerous medical applications including identifying diseases that have distinct odours, according to Shuguang Zhang, associate director of MIT's Centre for Biomedical Engineering and senior author of a study on the subject.
"Smell is perhaps one of the oldest and most primitive senses, but nobody really understands how it works," said Zhang. "It still remains a tantalising enigma."
In seeking to recreate smell, the MIT RealNose project seeks to recreate the most complex and least-understood of the five senses. Human smell systems are vast, including almost 400 functional genes, but dogs and mice far exceed human capacity, with around 1 000 functional olfactory receptor genes.
The variety of smell receptors allows humans and animals to discern tens of thousands of distinct odours. Individual odours activate multiple receptors. The multi-activation creates a signature that brains use to recognize particular odours.
"The main barrier to studying smell is that we haven't been able to make enough receptors," said MIT scientist Brian Cook, who recently defended his PhD thesis based on the work.
"Now, it's finally available as a raw material for people to utilise, and should enable many new studies into smell research," he said.
In the future, the RealNose team plan to work with researchers around the world to develop a portable microfluidic device that can identify various smells, including diseases with distinctive odours such as diabetes and lung, bladder and skin cancers.
The study will be released online this week by the Proceedings of the National Academy of Sciences (PNAS).