E-bandage generates electric field, reducing healing time

Scientists have developed an e-bandage that generates an electric field over a skin wound. The electric field dramatically reduced healing time for skin wounds in laboratory rats.

In this article, the ‘e‘ of e-bandage stands for ‘electric‘ and not ‘electronic.’ In most cases, as in e-commerce, e-learning, or e-meeting, the ‘e’ stands for ‘electronic.’

Our skin has a remarkable ability to heal itself. However, sometimes wounds heal extremely slowly, or even not at all. Slow healing puts the injured person at risk of scarring, infection, and chronic pain.

With this e-bandage however, skin injuries heal significantly faster, thus reducing the risk of infection and complications.

The scientists wrote about their work and new e-bandage in the journal ACS Nano (citation below).

In animal tests with rats, the e-bandage reduced healing times from approximately two weeks to just three days. This was for untreated injuries.



Co-author, Xudong Wang, said:

“We were surprised to see such a fast recovery rate. We suspected that the devices would produce some effect, but the magnitude was much more than we expected.”

Dr. Wang is a Professor of Materials Science and Engineering at the University of Wisconsin-Madison. He is also Chair of Graduate Studies.

E-bandage image
With the e-bandage, the wound on a rat’s skin (top left) healed much faster than a wound under a control bandage (right). (Image: acs.org)

E-bandage heals with electricity

We have known for a long time that electricity can be good for skin healing. However, most electrotherapy units currently in use require bulky, cumbersome electrical equipment to deliver powerful jolts of electricity. The bulky equipment also has complicated wiring.

Co-author, Angela Gibson MD, said:

“Acute and chronic wounds represent a substantial burden in healthcare worldwide. The use of electrical stimulation in wound healing is uncommon.”

Dr. Gibson is an Assistant Professor in the Department of Surgery at UW-Madison. She is also Medical Director at UW Health Wound Healing Services.

In contrast with existing methods, the new e-bandage is significantly more straightforward.

Prof. Wang said:

“Our device is as convenient as a bandage you put on your skin.”

The e-bandage consists of small electrodes for the site of the injury. The electrodes are lined to a band holding nanogenerators, i.e., tiny energy-harvesting units. Patients wear the band around their torso.



The patient’s rib-cage naturally contracts and expands during breathing. This contraction and expansion powers the nanogenerators. They then deliver low-intensity electric pulses.

Prof. Wang said:

“The nature of these electrical pulses is similar to the way the body generates an internal electric field.”

Electrical pulses don’t harm healthy skin

The low-power pulses in the e-bandage does not harm healthy skin tissue. Traditional, high-power electrotherapy devices, on the other hand, might harm healthy skin tissue.

In fact, the research team showed that cells that were exposed to high-energy electrical pulses produce nearly five times more reactive oxygen species compared to cells that were exposed to the nanogenerators. Reactive oxygen is a major risk factor for cellular aging and cancer.

A UW-Madison press release added:



“Also a boon to healing: They determined that the low-power pulses boosted viability for a type of skin cell called fibroblasts, and exposure to the nanogenerator’s pulses encouraged fibroblasts to line up (a crucial step in wound healing) and produce more growth factors.”

Weibo Cai said:

“These findings are very exciting. The detailed mechanisms will still need to be elucidated in future work.”

Dr. Cai is a Professor of Radiology at UW-Madison.

Citation

Effective Wound Healing Enabled by Discrete Alternative Electric Fields from Wearable Nanogenerators,” Yin Long, Hao Wei, Xudong Wang, Jun Li, Guang Yao, Xudong Wang, Bo Yu, Dalong Ni, Angela LF Gibson, Weibo Cai, Xiaoli Lan, and Yadong Jiang. ACS Nano. Publication date: November 29, 2018. DOI: 10.1021/acsnano.8b07038.