Smell is one of the most complex and least understood senses. Humans have about 400 olfactory receptor genes which enable us to smell tens of thousands of distinct odors.
Imagine using artificial noses to sniff out explosives and drugs in the future instead of using our good old trusty guard dogs. These devices can be used to identify an array of distinct odors and will be useful in early diagnosis of diseases that produce distinct odors, like diabetes. MIT biological engineers have found a way to mass produce smell receptors in the lab! Read about this on ScienceDaily: ‘Artificial Nose’ Progress: Engineers Mass-Produce Smell Receptors.