Consuming too much salt raises blood pressure, so to help monitor salt intake, researchers at the Woodruff School of Mechanical Engineering at the Georgia Institute of Technology have developed a flexible and stretchable wireless sensing system that can be comfortably worn in the mouth to measure the amount of sodium a person consumes. Based on an ultrathin, breathable elastomeric membrane, the sensor pairs with a system using Bluetooth technology to transmit sodium-consumption data to a smartphone or tablet. The researchers plan to further miniaturize the system, which now resembles a dental retainer, to the size of a tooth.
“We can unobtrusively and wirelessly measure the amount of sodium that people are taking in over time,” says Woon-Hong Yeo, an assistant professor in the Woodruff School of Mechanical Engineering at the Georgia Institute of Technology. “By monitoring sodium in real-time, the device could one day help people who need to restrict sodium intake and learn to change their eating habits and diet.” The device has been tested in three adult study participants who wore the sensor system for up to a week while eating both solid and liquid foods including vegetable juice, chicken soup, and potato chips.
Key to development of the intraoral sensor was replacement of traditional plastic and metal-based electronics with biocompatible and ultrathin components connected using mesh circuitry. Sodium sensors are available commercially, but Yeo and his collaborators developed a flexible micro-membrane version to be integrated with the miniaturized hybrid circuitry.
The flexible design began with computer modeling to optimize the mechanical properties of the device for use in the curved and soft oral cavity. The researchers then used their model to design the actual nanomembrane circuitry and choose components.
The device can monitor sodium intake in real-time, and record daily amounts. Using a smartphone or tablet application, the system could advise users planning meals how much of their daily salt allocation they had already consumed. The device can communicate with a smartphone up to ten meters away.