Increasingly, smart technologies are being designed for personalised healthcare. These take advantage of breakthroughs in sensing technologies for data acquisition, computing architectures for data processing and decision-making support, often based on artificial intelligence algorithms. For these devices to work, each smart component has to link through an interface, acting as a bridge between the biosystems monitoring physical parameters and the information processing systems which record and respond to that information. The CyberCare project, supported by the European Research Council, has designed and tested such a system, ultimately intended to go beyond monitoring health conditions and towards providing appropriate therapeutic options. “The central challenge was to develop not only a safe and accurate system, but one that users would adopt because it is unobtrusive and simple to use,” remarks project coordinator Giovanni De Micheli. The project successfully produced a prototype of a wearable device able to measure multiple ions in small samples of sweat.
The microfabricated integrated wearable solution
Ions are atoms, or groups of atoms, that hold a positive or negative electric charge. Quantifying their concentrations in bodily fluids indicates the presence of chemical compounds which can reveal a lot about health. Lithium levels, for example, are regularly monitored in people diagnosed with bipolar behaviour due to its role in mood stabilisation. In sports medicine, the balance of sodium and potassium is often measured after physical exertion, as these electrolytes help cells communicate with each other and so are fundamental to a lot of our bodily functions. At the heart of the wearable solution is a modular arrangement of sensing cells, covered by ion-selective membranes, permeable to specific ions of interest. Each sensing cell gathers the electrical charges from the ions. Measurements of these charges are then used to characterise the ions of interest. Cell arrays with different ion-specific membranes enable various substances to be detected in parallel. The sensors are integrated into a flexible foil, with the electronics for data acquisition mounted on a flexible substrate making it easier to attach to the body. Users are ultimately able to visualise and record results on a mobile device (such as a phone or a laptop), thanks to a wireless connection with the device, helping users, or health practitioners, choose the best treatments. “The system’s modularity allows versatility and reduced engineering costs,” says De Micheli. A dedicated system for monitoring sports activity and fatigue was tested by volunteers who were cycling while wearing a headband containing the CyberCare platform. The system analysed their sweat in real time, checking their sodium and potassium levels. “Comparing our results against measurements from standard sweat sampling and offline analysis with bulky lab equipment, we found an almost perfect match,” explains De Micheli.
CyberCare’s device helps support the EU’s Digital Health goal of strengthening citizen empowerment and individual care through digital services, with applications like this helping to facilitate remote health monitoring and support. Additionally, it could help recreational and professional athletes to optimise their training. Currently the technology remains at the prototype stage while the team look for a suitable industrial vendor to develop a marketable product for either medical or sports applications. “With so many biological compounds offering useful health indicators, this technology can be integrated into many applications. As well as monitoring organic health, it could also be used, for example, to measure exposure to pollutants, such as lead,” concludes De Micheli.
CyberCare, wearable, ion, sweat, health, potassium, sodium, sports, sensor