The new device, designed by North Carolina State University, is lightweight. It suits a range of people through being flexible and stretchable. The prototype devices have been designed to be worn on the wrist or as a chest patch. It is the latest in medical and healthcare orientated wearable devices. Recently Digital Journal reported on a new wearable designed to measure blood pressure.
While the idea of a hydration monitor, giving real-time information to the wearer, is a good one, the design and technological development was complex. The special is made up of two electrodes contained within an elastic polymer composite. This structure contains conductive silver nanowires. These electrodes are intended to monitor the electrical properties of the skin. This is key to the measure of hydration, since the skin’s electric properties change in a fairly predictable in accordance with hydration and dehydration. This allows the collected readings from the electrodes to signal how hydrated the skin is.
The device has undergone rigorous laboratory testing. This was first undertaken using custom-made artificial skins. These skins were rendered to have a wide spectrum of hydration levels and readings matched those of large-scale, established hydration monitors. The researchers also varied the surrounding environment, and noted that the performance of the wearable device and its sensor was not affected by ambient humidity, meaning that it can be worn throughout the world.
To enable users to have a choice of formats, the sensor was incorporated into two different wearable systems. These took the form of a wristwatch and an adhesive patch, intended to be worn on the chest. Either fitting is designed to send a wireless signal to computer software held on a mobile device. This allows either the user or another person (such as a healthcare professional) to monitor hydration readings.
The sensor has been designed to be relatively inexpensive, at less than $1. This doesn’t mean, however, the cost will be this low when the device is commercialized.
In a research note, one of the lead scientists behind the project, Professor Yong Zhu explains the application further: “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 moisturizers are for cosmetics.”
The new device has been described in the journal Advanced Healthcare Materials. The research paper is titled “A Wearable Hydration Sensor with Conformal Nanowire Electrodes.”
