Wearable hydration skin sensor advises athletes about optimum refreshment
A new wearable sensor capable of measuring the level of skin hydration could tell athletes or workers in hot environments when to replenish fluids in order to avoid dehydration.
The technology has been developed by a team from North Carolina State University, USA. It uses two electrodes monitoring the electrical properties of the skin, which change with the level of hydration.
“We have developed technology that allows us to track an individual's skin hydration in real time,” said Yong Zhu, an associate professor of mechanical and aerospace engineering at NC State.
“Our sensor could be used to protect the health of people working in hot conditions, improve athletic performance and safety and to track hydration in older adults or in medical patients suffering from various conditions. It can even be used to tell how effective skin moisturisers are for cosmetics.”
The electrodes of the wearable prototype, described in the latest issue of the journal Advanced Healthcare Materials, are made of an elastic polymer composite containing silver nanowires.
The device is lightweight, flexible and stretchable and can be worn on the wrist or as a chest patch. Both the wristband and the patch transmit data wirelessly to a laptop, tablet or smartphone running a special app. This provides the possibility of accessing the real-time data remotely, allowing a third party to monitor the person’s state, which could be beneficial in military or medical settings.
The researchers tested the wearable gadgets in laboratory conditions using custom made artificial skins with different levels of hydration. They found that the new devices were as accurate as a commercially available but much more expensive hydration monitor.
“The commercially available monitor we tested our system against costs more than $8,000,” said Shanshan Yao, a Ph.D. student at NC State and lead author of the paper. “Our sensor costs about one dollar and the overall manufacturing cost of the wearable systems we developed would be no more than a common wearable device, such as a Fitbit.”