Smart Bandage Monitors Wounds Without Batteries

Things can go from bad to worse very quickly in wound care. Without the normal protective barrier of the skin, infections or inflammation can rapidly appear. These complications may become very serious if left untreated, so one of the keys to proper wound care is frequent monitoring. The appearance or temperature of the wound gives medical professionals a pretty good idea as to the condition of the wound, but since the tissue is dressed and bandaged, it cannot be checked on very often — at least not without painful and time-consuming rebandagings.

Wearable electronic medical devices could provide continuous streams of relevant data. However, the sensing equipment would need to be safe and comfortable for direct contact with the wound. Moreover, the batteries would need to be small — for patient comfort — and very long-lasting — for patient convenience. To date, checking all of these boxes has been a big challenge. But recently a team at the Universitat Rovira i Virgili in Spain has put forward a solution that meets all the criteria. They have developed an intelligent bandage that is capable of continually monitoring skin temperature, all without batteries or any external source of power.

The device is built around a flexible thermoelectric (TE) sensor system that harvests energy from the temperature difference between the skin and surrounding environment. This technology uses an array of thermocouples — junctions of semiconductor materials — to generate electrical signals in response to small temperature changes on the skin’s surface. This arrangement provides both power and sensing capabilities, all in one.

It has been demonstrated that the device can detect temperature shifts as small as 0.4°C, and the array of thermocouples make it possible to map out the temperature at specific points all throughout a wound. Feedback is nearly instant, with temperature changes being reported within three seconds.

Designed with patient comfort in mind, the device is printed on flexible polymer substrates using techniques similar to T-shirt printing. This makes it lightweight, stretchable, and highly adaptable to the contours of the human body. It can be worn for days without discomfort, and it remains functional even after hundreds of bending cycles.

Unlike conventional infrared cameras or single-point sensors, which require patient immobilization and cannot track temperature variations across large areas, this new TE sensor offers wide-area, continuous monitoring. It produces easy-to-interpret color maps of skin temperature, allowing even non-specialist healthcare workers to identify areas of concern quickly and accurately.

In addition to wound care, the team envisions broader applications for their technology in the future. The device could be used to monitor pressure ulcers, track inflammation in chronic conditions, or be integrated into medical kits for field use. The researchers are also exploring ways to expand the device’s capabilities, such as incorporating biosensors to detect other physiological markers.

If this work makes it out of the research lab, the future of wound care may involve fewer painful rebandagings and more proactive, comfortable monitoring — helping to catch complications before they become a serious concern.