The olfactory system is one of the oldest and definitely the most complex of a human's sensory equipment. It is not; however, anywhere near the most complex as far as Earth-based life goes.
A human's olfactory system is driven by about 400 active genes, which express proteins called olfactory receptors. By comparison, mankind's faithful canine companions have over 1,000 of these task specific genes dedicated to their sniffing abilities.
The complexity of the olfactory system has kept it one of the least understood biological systems. To compound this, olfactory proteins are remarkably difficult to study outside of the body as their composition makes them hydrophobic and causes them to lose their structure in water-based solutions.
A group at the Massachusetts Institute of Technology may have solved this problem of delicate structures. The project, known as MIT RealNose, MIT in this case representing microfluidic-integrated transduction, has been able to successfully harvest the proteins by utilizing a hydrophobic detergent solution, wheat germ extract and a multi-step purification process. The scientists were able to successfully produce enough of the protein structures via the process to begin functional and structural analysis.
“The main barrier to studying smell is that we haven't been able to make enough receptors and purify them to homogeneity,” explains MIT student Brian Cook. “Now, it's finally available as a raw material for people to utilize, and should enable many new studies into smell research.”
Understanding the nose and the developing the ability to build them from the bottom up may help produce better detection systems for anything from dangerous chemicals to medical conditions. A remotely operated artificial nose could replace bomb-sniffing dogs, keeping them and their partners out of harm's reach.