Nanotechnology: A Gentle Introduction to the Next Big Idea

Electronic Noses

We looked at how biological noses work using molecular recognition to send a neural signal to the brain. In the artificial nose, the most common replacement for the nasal membrane is an electrically conducting polymer. When the polymer is exposed to any given molecule in the vapor phase, its conductivity will change a little bit. In the electronic nose, a random polymer, or mix of polymers, is spread between electrodes. When the molecules to be smelled land on the polymer(s), the conductivity properties in particular regions will change in a particular way that is specific to any given analyte. The nature of the detection is interesting, since it is based on so-called neural nets. The idea is that each sensor will give a particular ...