Researchers from Empa teamed up with ETH Zurich, Centre Suisse d’Electronique et de Microtechnique (CSEM) and University Hospital Zurich to develop a high-tech system that is supposed to supply the nursing staff with relevant data about the condition of a wound.
When wounds heal, the body produces specific substances in a complex sequence of biochemical processes, which leads to a significant variation in a number of metabolic parameters. All these variations can be detected with specialised sensors. With this in mind, Empa teamed up with project partner CSEM to develop a portable, cheap and easy-to-use device for measuring fluorescence that is capable of monitoring several parameters at once.
A novel bandage alerts the nursing staff as soon as a wound starts healing badly. Sensors incorporated into the base material glow with a different intensity if the wound’s pH level changes. This way even chronic wounds could be monitored at home. This would also mean a gentler treatment for patients, less work for the nursing staff and, therefore, lower costs: globally, around US$ 17 billion were spent on treating wounds last year, according to Empa.
The pH level is particularly useful for chronic wounds. If the wound heals normally, the pH rises to 8 before falling to 5 or 6. If a wound fails to close and becomes chronic, however, the pH level fluctuates between 7 and 8.
The idea behind the sensors is that if certain substances appear in the wound fluid, “customised” fluorescent sensor molecules respond with a physical signal. They start glowing and some even change colour in the visible or ultra-violet (UV) range. Thanks to a colour scale, weaker and stronger changes in colour can be detected and the quantity of the emitted substance be deduced.
