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Smart bandage improves wound healing in mice

Freely moving mice wearing the wireless smart bandages. Jiang et al., Nature Biotechnology

The skin has a remarkable capacity to regenerate itself after injury. This complicated process starts with inflammation and ends with the formation of new skin and scar tissue.

But wounds can get infected. And some diseases and conditions, such as diabetes and immunosuppression, may interfere with wound healing. Nonhealing wounds can lead to pain, loss of functioning, and even amputation or death. More than 6 million people in the U.S. alone are living with a chronic, nonhealing wound.

An NIH-funded research team at Stanford University led by Drs. Geoffrey Gurtner and Zhenan Bao has been testing technologies to encourage wound healing. In a new study, they designed a smart bandage to actively assist the healing process. They described their results on November 24, 2022, in Nature Biotechnology.

The smart bandage consists of an extremely thin, flexible printed circuit. A small, coiled antenna draws power wirelessly from a nearby source. This allows the bandage to provide electrical stimulation to injured tissue. Such stimulation has been shown to boost wound healing.

The wireless power also allows the bandage to monitor the skin underneath for signs of healing or infection. It does this by measuring temperature and how easily an electrical current passes through the area.

To stick the bandage to the skin, the researchers developed an adhesive gel that loosens when heated above body temperature. This allows it to be removed without causing damage to vulnerable skin. At normal skin temperature, the gel proved to be as sticky as a standard medical tape.

Healthy mice wearing the bandage moved normally, and the bandage was able to capture information about their skin during movement. No skin irritation was observed over a period of about two weeks.

Skin wounds on mice treated with electrical stimulation provided by the smart bandage healed about 25% more quickly than those covered with a standard sterile dressing. The new skin on the mice who got the smart bandage showed an increase in new blood vessels. It was also thicker and stronger than that on mice given standard bandages. Similar results were seen in mouse models of burn healing and diabatic wounds.

When the researchers examined cells from mice given the smart bandage, they found that certain types of immune cells had increased activity of genes involved in tissue regeneration. This was accompanied by increases in the corresponding proteins needed for healing processes.

“With stimulation and sensing in one device, the smart bandage speeds healing, but it also keeps track as the wound is improving,” explains Dr. Artem Trotsyuk, who helped lead the study.

“It is an active healing device that could transform the standard of care in the treatment of chronic wounds,” adds Dr. Yuanwen Jiang, who also helped lead the study.

Before the proof-of-concept bandage can be tested in people, several steps need to be taken. These include enlarging it to a human-sized version and testing it on larger animals before beginning human trials.

—by Sharon Reynolds