Worn on the wrist, the tracker could be used to monitor key chemical markers including glucose and lactose in athletes or military personnel. These metabolites can indicate flagging performance or potential health issues, enabling trainers or health professionals to intervene. The device, which includes a replaceable strip that contacts with the skin, can also measure temperature and pH.
"For this proof-of-concept study, we tested sweat from human participants and monitored for glucose, lactate, pH and temperature," said Michael Daniele, an engineering professor at North Carolina State University and co-corresponding author of a paper on the work, published in Biosensors and Bioelectronics.
"The device is the size of an average watch but contains analytical equipment equivalent to four of the bulky electrochemistry devices currently used to measure metabolite levels in the lab. We've made something that is truly portable, so that it can be used in the field."
The replaceable strip on the back of the device is embedded with chemical sensors. Data from these sensors is interpreted by hardware inside the wrist device, which then records the results and relays them to a user's smartphone or smartwatch.
According to Daniele, it costs just tens of dollars to produce the metabolite tracker, but it’s hard to predict what it might cost customers. He said the cost of the replaceable sensor strips should be comparable to the glucose strips used by diabetics. The team’s priorities will now be to test the device's longevity and seek industry partners to develop a commercial product.
"We want to confirm that it can provide continuous monitoring when in use for an extended period of time,” said Daniele.
"We're optimistic that this hardware could enable new technologies to reduce casualties during military or athletic training, by spotting health problems before they become critical. It could also improve training by allowing users to track their performance over time. For example, what combination of diet and other variables improves a user's ability to perform?”