Tiny sensor can send information from a tooth

A tiny sensor has been developed that can be attached to a tooth and send back health information to its user.

We have seen a wide variety of innovations in developing sensors for monitoring health. These include a tattoo that can track biometric data and an ingestible sensor that connects to your phone. But it can be difficult to accurately track what is going on inside our bodies. That may be about to change, with the introduction of miniaturised sensors developed by researchers at the Tufts University School of Engineering. The sensors are designed to be mounted on a tooth and communicate wirelessly with a mobile device. They are capable of transmitting information on the intake of substances such as glucose, salt and alcohol. This could one day enable the detection of a wide range of nutrients and physiological states.

The new sensors are made up of three layers. A central ‘bioresponsive’ layer that can absorb different substances, which are sandwiched between two outer layers of square-shaped gold rings. Together, the three layers act like a tiny antenna, collecting and transmitting radio waves in different frequencies, depending on the substance detected. For example, if the central layer absorbs salt, its electrical properties will change. The sensor will then receive and transmit a different spectrum of radiofrequency waves. By determining the frequency of radio waves being absorbed and emitted by the sensor, different substances can be detected and measured.

According to Tufts researcher Fiorenzo Omenetto, “We have extended common RFID [radio frequency identification] technology to a sensor package that can dynamically read and transmit information on its environment, whether it is affixed to a tooth, to skin, or any other surface.” Omenetto also points out that the bioresponsive layer in the sensor can be modified to target a variety of different substances. In the future, tiny sensors like these could also be used to track our internal health. What other uses might there be for sensors that can be worn on a tooth?