Olfaction on a chip

On-chip sensing of physical signals is now relatively straightforward, with on-chip tilt sensors and cell phone cameras now ubiquitous, but sensing of odorants has proven to be far more challenging. A general purpose, mobile electronic nose would address pressing needs in security and food safety. We demonstrate here an approach that combines living olfactory sensory neurons (OSNs) with integrated circuitry. The hybrid bio-electronic chip harnesses the as-yet unparalleled capabilities of olfactory sensory neurons - in variety, selectivity, and ability to function in the real world - and takes advantage of modern silicon chip technology for detecting and processing electrical signals. OSNs were cultured directly over an array of electrodes on the surface of a custom integrated circuit so that the signals, a series of “spikes” upon odorant binding, could be locally detected and processed. Consistent and selective responses to specific odorants were recorded from individual neurons.