Chapter 7. Sensors

In this chapter…

• Natural Nanoscale Sensors

• Electromagnetic Sensors

• Biosensors

• Electronic Noses

Imagine supermarket packaging that could tell instantaneously if the food inside had been exposed to heat or had begun to spoil. Imagine a tiny foolproof automatic indicator that could constantly monitor a home for dangerous chemicals such as gas leaks, carbon monoxide, or ozone. Imagine a simple swab test that would instantly tell whether a patient has strep, diabetes, various genetic diseases, the flu, or an anemia. Imagine a simple wire that could be inserted in the ground to tell a home gardener where the soil is best for planting cucumbers. Imagine a foolproof (and it would need to be) explosives test so that you wouldn't need to remove all your clothes at the airport. All these possibilities are potential applications of nanoscale sensors. Sensors are structures that indicate the presence of particular molecules or biological structures, as well as the amounts that are present. Sensors are already present throughout our society, but the best sensors will be made from nanostructures and, for starters, should revolutionize much of the medical care and the food packaging industries.