Researchers have developed an integrated wireless mouth guard biosensor for real-time monitoring of health markers in saliva.
Engineers at the UC San Diego have developed a smart mouth guard capable of monitoring health markers, such as lactate, cortisol and uric acid, in saliva and transmitting the data wirelessly to a mobile device. The idea is that, one day, the technology could be used to keep tabs on patients without invasive procedures, as well as track athletes’ performance or stress levels in soldiers and pilots.
The study, which was led by UC San Diego professors Joseph Wang and Patrick Mercier, focused primarily on uric acid, which is a marker related to diabetes and gout. Currently, the only way to monitor these levels in a patient are through blood tests. Wang explains, “The ability to monitor continuously and non-invasively saliva biomarkers holds considerable promise for many biomedical and fitness applications.”
The team of researchers developed a screen-printed sensor using silver, Prussian blue ink and uricase. To ensure that the sensors only reacted with the uric acid, the nanoengineers had to set up the chemical equivalent of a two-step authentication system. The first step involves a series of chemical keyholes that allows only the smallest biochemicals to enter inside the sensor. The second step is a layer of uricase trapped in polymers. The reaction between acid and enzyme generates hydrogen peroxide, which is detected by the Prussian blue ink.
That information is then sent to a circuit board as electrical signals via metallic strips that are part of the sensor. The board, which is no much bigger than a penny, is equipped with a microcontroller, a Bluetooth Low Energy transceiver, and a potentiostat. These small chips detect the sensor output, digitizes it and wirelessly relays the data over to a smartphone or computer.
Thus far, the researchers have been able to show that the mouth guard sensor could offer an easy, more reliable way to monitor uric acid levels; however, it has only been tested with human saliva and not yet actually in a person’s mouth. Looking ahead, the team plans to embed all of the electronics inside the wearable device so that it can be worn. This process will entail testing the various sensors and electronic materials to ensure their biocompatibility.
The next iteration of the mouth guard is expected to be completed in a year or so. Until then, you can read all about the study in its recently published article in Biosensors and Bioelectronics.
(Image: UC San Diego, Jacobs School of Engineering)