Used since 2013, electroceutical bandages — which use electrical impulses to treat medical issues — kill bacteria around a wound, allowing wounds to heal faster. In addition, if infection is present, they can remove the infection, enabling them to heal chronic wounds.
Biofilms are small communities of microorganisms — including bacteria — that can live on the surface of the skin or a wound. The communities are held together by extracellular polymeric substances (EPS) made up of fats and proteins. The EPS can create a protective barrier that keeps bacteria safe from traditional clinical treatment options including antibiotics. That means that even with traditional antibiotic treatments, some skin infections can linger and prevent wounds from healing. But electroceutical bandages made of the right materials can break through that barrier, destroying bacteria and allowing wounds to heal faster.
Researchers used haboti silk, a common Japanese weave, in the bandages. They silk-screened silver lines onto the silk and attached a small device to deliver electricity to the biofilm. When the electrified bandage was applied to bacteria-laden biofilm in the lab, the bacteria were destroyed. The electric current disrupted the biofilm enough to begin destroying bacteria. In addition, bacteria continued to die off two days after the electric current was turned off. The theory, based on these experiments, is that the bandage and electric current produce a potent antimicrobial chemical — hypochlorous acid — that takes over and kills bacteria without harming the healthy skin nearby.
This work was conducted on bacteria and biofilms in vitro — meaning in a petri dish rather than on a human or an animal. The work sets the stage for experiments that will help scientists better understand the reasons why biofilms work the way they do. That fundamental understanding will help improve the design of electroceutical bandages.