Researchers have developed an inexpensive bandage that uses an electric field to promote the healing of chronic wounds. In animal tests, wounds treated with these electric bandages healed 30% faster than wounds treated with conventional bandages.
Chronic wounds are open wounds that heal slowly, if at all. For example, the sores that appear in some patients with diabetes are chronic wounds. These wounds are especially problematic because they often recur after treatment and significantly increase the risk of amputation and death.
One of the challenges associated with chronic wounds is that existing treatment options are extremely expensive, which can create additional problems for patients.
“Our goal here was to develop a much more affordable technology that would speed healing in patients with chronic wounds,” says Amay Bandodkar, co-author of the paper and an assistant professor of electrical and computer engineering at North Carolina State University. “We also wanted to make sure the technology was easy enough for people to use at home, rather than something patients can only receive in clinical settings.”
“This project is part of a larger DARPA effort to accelerate wound healing with customized wound dressings,” said co-author Sam Sia, a professor of biomedical engineering at Columbia University. “This collaborative project demonstrates that these lightweight bandages, which can provide electrical stimulation simply by adding water, heal wounds faster than the control, at a rate similar to bulkier and more expensive wound treatments.”
Specifically, the research team has developed water-powered electronics-free (WPED) dressings, which are disposable wound dressings that have electrodes on one side and a small biocompatible battery on the other. The dressing is applied to the patient so that the electrodes come into contact with the wound. A drop of water is then applied to the battery, which is activated. Once activated, the dressing produces an electric field for several hours.
“That electric field is critical, because it’s well established that electric fields accelerate the healing of chronic wounds,” says Rajaram Kaveti, co-senior author of the study and a postdoctoral researcher at NC State.
The electrodes are designed so that they can bend with the bandage and adapt to the surface of chronic wounds, which are often deep and irregularly shaped.
“This adaptive ability is critical because we want the electrical field to be directed from the periphery of the wound toward the center of the wound,” Kaveti says. “To effectively focus the electrical field, the electrodes need to be in contact with the patient at both the periphery and the center of the wound. And because these wounds can be asymmetrical and deep, we need electrodes that can adapt to a wide variety of surface characteristics.”
“We tested the dressings in diabetic mice, which are a commonly used model for human wound healing,” said Maggie Jakus, co-senior author of the study and a graduate student at Columbia. “We found that electrical stimulation from the device accelerated the rate of wound closure, promoted the formation of new blood vessels, and reduced inflammation, all of which indicate an overall improvement in wound healing.”
Specifically, the researchers found that mice that received WPED treatment healed about 30% faster than mice that received conventional bandages.
“But it’s equally important that these dressings can be produced at a relatively low cost – we’re talking about a couple of dollars per dressing in overhead,” Bandodkar says.
“Diabetic foot ulceration is a serious problem that can lead to lower extremity amputations,” said Aristidis Veves, co-author of the study and professor of surgery at Beth Israel Deaconess Center. “There is an urgent need for new therapeutic approaches, as the last one approved by the Food and Drug Administration was developed more than 25 years ago. My team is very fortunate to be involved in this project investigating innovative and efficient new techniques that have the potential to revolutionize the treatment of diabetic foot ulcers.”
Additionally, WPEDs can be applied quickly and easily. Once applied, patients can move around and participate in their daily activities. This functionality means that patients can receive treatment at home and are more likely to comply. In other words, patients are less likely to skip treatment sessions or take shortcuts since they do not have to visit a clinic or remain immobile for hours.
“Our next steps include continuing to work on refining our ability to reduce the fluctuations in the electric field and extend its duration. We are also conducting further testing that will bring us closer to clinical trials and ultimately to practical use that can help people,” Bandodkar said.
The paper, “Electronics-free, water-powered dressings that electrically stimulate wounds for rapid wound closure,” will be published August 7 in the open-access journal Scientific advancesCo-authors on the paper include Henry Chen, an undergraduate student in the joint NC State-UNC department of biomedical engineering; Bhavya Jain, Navya Mishra, Nivesh Sharma and Baha Erim Uzuno?lu, PhD students at NC State; Darragh Kennedy and Elizabeth Caso of Columbia; Georgios Theocharidis and Brandon Sumpio of Beth Israel Deaconess Medical Center; Won Bae Han of Korea University and the Georgia Institute of Technology; Tae-Min Jang of Korea University; and Suk-Won Hwang of Korea University and the Korea Institute of Science and Technology.
This work was supported by the Defense Advanced Research Projects Agency under grant D20AC00004 and the Center for Advanced Self-Powered Sensor Systems and Integrated Technologies at NC State, which is funded by National Science Foundation grant 1160483. Bandodkar and Kaveti are inventors on a patent application related to this work.