Wireless sensors are ubiquitous, providing a steady stream of information on anything from our physical activity to changes occurring in the world's oceans. Now, scientists have developed a tiny form of the data-gathering tool, designed for an area that has so far escaped its reach: our teeth.
The 2-millimeter-by-2-millimeter devices (pictured) are made up of a film of polymers that detects chemicals in its environment. Sandwiched between two square-shaped gold rings that act as antennas, the sensor can transmit information on what's going on—or what's being chewed on—in our mouth to a digital device, such as a smartphone. The type of compound the inner layer detects—salt, for example, or ethanol—determines the spectrum and intensity of the radiofrequency waves that the sensor transmits. Because the sensor uses the ambient radio-frequency signals that are already around us, it doesn't need a power supply.
The researchers tested their invention on people drinking alcohol, gargling mouthwash, or eating soup. In each case, the sensor was able to detect what the person was consuming by picking up on nutrients, the researchers will report next week in Advanced Materials.
The devices could help health care and clinical researchers find links between dietary intake and health and, in the long run, allow each of us to keep track of how what we consume is affecting our bodies.