The days of ripping off a Band-Aid could soon be in the past, with scientists creating a new affordable, flexible electronic covering that not only speeds and wirelessly monitors healing but performs a disappearing act by being harmlessly absorbed into the body when its job is done.
“Although it’s an electronic device, the active components that interface with the wound bed are entirely resorbable,” said Northwestern University’s John A. Rogers, who co-led the study. “As such, the materials disappear naturally after the healing process is complete, thereby avoiding any damage to the tissue that could otherwise be caused by physical extraction.”
Electronic bandages are an emerging but by no means new technology, with earlier developments into bacteria-killing patches, motion-powered covers and even forays into smart dressings. But this dressing is the first bioresorbable bandage of its kind, delivering electrotherapy to wounds to accelerate healing by up to 30 per cent, and relaying data on the injured site's condition to allow monitor of it from afar. The Northwestern scientists believe it could be a game-changer for diabetics and others who face serious complications from frequent and slow-healing sores.
“When a person develops a wound, the goal is always to close that wound as quickly as possible,” said Northwestern’s Guillermo A. Ameer, co-lead on the study. “Otherwise, an open wound is susceptible to infection. And, for people with diabetes, infections are even harder to treat and more dangerous. For these patients, there is a major unmet need for cost-effective solutions that really work for them. Our new bandage is cost-effective, easy to apply, adaptable, comfortable and efficient at closing wounds to prevent infections and further complications.”
This wireless, battery-free bandage softly wraps around the wound, with a flower-shaped electrode that sits on top of the injury site and a ring-shaped electrode that surrounds it on the healthy tissue. On the other end of the bandage, an energy-harvesting coil powers the electrodes and a near-field communication system wireless transmits data from the device in real time.
In the study on mice, researchers applied electrotherapy for 30 minutes a day, and results showed wounds closed up to 30% faster. During this, the wound can be monitored wirelessly, measuring the resistance of the electrical current. If the current measurement remained high, this could alert the patient’s physician to the fact the wound wasn’t healing accordingly and intervene.
“As a wound tries to heal, it produces a moist environment,” Ameer said. “Then, as it heals, it should dry up. Moisture alters the current, so we are able to detect that by tracking electrical resistance in the wound. Then, we can collect that information and transmit it wirelessly. With wound-care management, we ideally want the wound to close within a month. If it takes longer, that delay can raise concerns.”
The team wanted to develop a bandage that would not need removal, and found that when the transition metal molybdenum is thin enough, it can biodegrade. Molybdenum, common in semiconductors and electronics, is also found in many foods. When the wound has sufficiently healed, the flower-shaped electrode sitting on the sensitive site dissolves and is absorbed, causing no distress to the skin.
“We are the first to show that molybdenum can be used as a biodegradable electrode for wound healing,” Ameer said. “After about six months, most of it was gone. And we found there’s very little accumulation in the organs. Nothing out of the ordinary. But the amount of metal we use to make these electrodes is so minimal, we don’t expect it to cause any major issues.”
Researchers now plan to test the smart healer on diabetic ulcers in larger animals, before ideally moving on to a human study.
The research was published in journal Science Advances, and Ameer discusses the electronic bandage in the video below.
Source: Northwestern University
