According to the research published in the journal Nature, when the device is placed on a person’s brow or wrist via a sweat band it at can read the molecular composition of sweat and then send the results in real time to a smartphone.
Such technology could be useful in providing early warning of changes in the human body, such as dehydration, chemical exposures, muscle fatigue and chronic stress, and even help manage diseases such as diabetes.
“Sweat provides us with a wealth of information about our body condition because it consists of a wide spectrum of chemicals,” said lead author of the study, Ali Javey. “We have developed an array of sensors that can detect and analyse multiple chemicals simultaneously in real time, and we have also developed the computation that goes along with it.”
For their first generation of sweat-scanning wearables, Javey and his team decided to track four different chemicals: sodium, potassium, glucose and lactate.
“Monitoring electrolytes such as sodium and potassium may help track conditions like dehydration,” said Javey. “Meanwhile lactate levels may be useful for tracking muscle fatigue, and glucose may help monitor blood sugar levels.”
The wearable’s sensors are made from a flexible electronics board joined to a flexible printed plastic sensor array. When the sensors come into contact with sweat they generate electrical signals that are amplified and filtered, and then calibrated using skin temperature.
“Electrochemical sensors are very sensitive to temperature, and skin temperature can vary quite a bit when we are sweating,” said Javey. The data is then wirelessly transmitted to a smartphone.
The device was tested among 26 healthy adults while they did workouts of various intensities and lengths of time, indoors and outdoors. When compared with sweat data measured by standard lab tests, the researchers found the wearable’s data was accurate and potentially helpful for health monitoring.
Jarvey and his team of researchers are currently embarking on bigger studies and exploring other types of sensors to plug into their wearable.