A smart bandage that can monitor chronic wounds and help them heal has been developed by scientists who say it could aid people with diabetic ulcers, burns and non-healing surgical wounds.
According to the figures from 2018 there are 2.2 million people in the UK with chronic wounds, costing the NHS 5.3 billion a year.
A stretchable, wireless, bioelectronic system that can stick to skin is something researchers say they have come up with a device that could help such wounds heal.
Dr Wei Gao, a co-author of the research from the California Institute of Technology, said the device consists of two parts a reusable flexible printed circuit board and a disposable patch. The disposable patch contains biosensors, electrodes, and drug-loaded hydrogels. Biosensors can help identify features of the wound such as its temperature, pH, and levels of substances such as glucose, uric acid and lactate metrics, which provide important insights into whether the wound is infected and its levels of inflammation.
The technique that allows for electrical stimulation to encourage wounds to heal but has been hampered by bulky equipment. It allows the controlled release of anti-inflammatory and antimicrobial drugs.
Gao said all the signals can be sent wirelessly to a user interface such as a computer or a cellphone. By applying electrical potential, we can wirelessly control the drug release. The team found that the devices could detect features such as temperature, glucose levels and pH of wound fluid, as well as the wounds of diabetic mice and rats before and after infection. Before and after the mice were given treatment, these measurements changed as expected.
Mice with smart bandages who experienced both drug release and electrical stimulation showed higher wound closure and less scarring than mice with scarring wounds that were not covered by the bandages.
The team says that the smart bandage can be used for one to two weeks and will cost tens of dollars for the reusable electronics part of the device, and a few dollars for a disposable patch.
Gao said it was hoped that smart bandages could be used in clinics in the next five to 10 years, and that further work is needed, including studies with pigs and humans.
Dr Jenna Cash, principal investigator of the skin wound research group at the University of Edinburgh, who was not involved in the research, said the study was a beautiful piece of work. She said that the idea is really exciting and a great step forward.
Cash said that the conundrums remain: Part of the issue we have with chronic wounds is that we don't understand the mechanisms by which they form. It's hard to figure out how to reverse that process without us understanding the precise cellular and molecular mechanisms behind their formation and persistence. Cash said that the new devices' measurements will be relevant to true chronic wounds in humans, given that they may already be infected when the monitoring system is applied and may not heal as the rodent wounds did. Chronic wounds can show great variability in size and the amount of fluid they produce.
She said it is an exciting advance, but it will need a lot of development going forward to make it work as intended in people.