A new smart bandage, which can be used to tell doctors when a cut has healed, can be applied without the need for them to do so.
The bandage, developed by scientists at the University of Bologna, Italy, is equipped with a sensor to read moisture levels — a crucial indicator of if a wound has healed — and transmits the data to an app on a nearby smartphone.
This information allows doctors to ensure that a wound is healed without having to remove the bandage. This can often slow down the healing process.
By providing real-time wireless monitoring, the technology could help doctors better monitor wounds, according to the experts – although it’s just a prototype for now.
Researchers have not yet revealed the cost of the smart bandage, or when it might become commercially available. However, they said that it was ‘low-cost and disposable’ because they used inexpensive materials in their design.
With the new prototype, doctors can make sure a dressed wound is healing without taking off the bandage, based on moisture level information. The healing process can be disrupted if a bandage is removed.
The smart bandage uses commercially-available bandage materials. The smart bandage uses commercially-available materials. However, it has a sensor that measures changes in the moisture content of a wound. It also contains a radio frequency identification (RFID), chip that transmits data to a smartphone.
Dr. Luca Possanzini from the University of Bologna said, “We developed a range of bandsages with different layers and differing absorption properties and characteristics.”
“The idea is that every type of wound could have its appropriate dressing, from slow-exuding wounds to high-exuding wounds like burns and blisters.
“But, before we can apply our technology for different types of wounds, we will need more optimization of the sensor geometries and the appropriate sensor values.
The’smartbandage’ is equipped with a sensor to measure the moisture levels of wounds and then transmits that information to a nearby phone using a radio-frequency ID (RFID) chip.
Wireless communication with a smartphone allows for real-time measurements of the wound’s condition.
The RFID chips (pictured) measure approximately the same size as a grain or rice grain and are used in clothing security tags (stock image).
RFID chips are about the same size as a grain of rice and are already used in clothing security tags and contactless cards – including Transport for London’s Oyster card.
There are many factors that influence whether or not a wound heals. These include temperature, acidity, glucose levels, pH and, most importantly, moisture.
Too dry can cause skin tissue to become dry. However, too wet can cause it to become irritated and can lead to a loss of moisture.
A doctor may need to remove a bandage if they want to test the moisture levels of a wounded area. This could cause irreparable damage to the delicate healing tissue.
The researchers created a smart gauze to monitor wound moisture levels non-invasively.
The team had to choose from a variety of materials because bandages must be biocompatible, disposable, and affordable.
They applied a conductive polymer called PEDOT:PSS onto two different types of gauzes – gauze rayon and gauze PET – using a technique called screen printing.
Gauze is a thin transparent fabric, wrapped around a wound or fracture as a surgical dressing.
The conductive polymer appears in the form of a length of what looks to be ink, printed in a straight line through the middle.
A conductive polymer, PEDOT:PSS, is screen printed onto gauze (pictured), according to the researchers (stock photo).
The sensor is attached to a patient and the idea is that any changes in the moisture levels of the wound will cause a change in the electrical signal measured by it.
Dr Marta Tessarolo of the University of Bologna, study author, said that the organic semiconducting polymer PEDOT:PSS can be easily deposited on many substrates as standard ink.
“We also integrated a cheap, disposable, and bandage compatible RFID tag, similar those used for clothing security labels, into the textile patches.
“The tag can wirelessly communicate moisture levels with a smartphone to allow healthcare staff to know when a dressing needs to be changed.”
Graphical abstract taken from the paper. (A) Cross-section of rayon and gauzes PET. (B) Image of final textile moisture sensor. (C) A diagram of the bandage sensor that shows the three layers of composition. (D) Top and cross sections of the two absorb layers.
To form a protective and absorbing layer, commercially available gauze materials could also be used.
To test their bandages, the researchers exposed them to an artificial version of exudate – the liquid that seeps from wounds – and also tested different bandage materials and shapes.
The bandage was extremely sensitive and gave different readings depending on whether the wound was wet, moist, or saturated. This suggests that it could be a useful tool for wound management.
Researchers may be able, in the future, to modify the bandage’s geometry and materials to adapt to different types of wounds.
The study has been published in the journal Frontiers in Physics.