A team of researchers from Sweden’s Linköping University has developed a color-changing nanocellulose wound dressing.

According to its developers, the dressing will change color to indicate that the wound is infected without interfering with the healing process.

Source: Linköping University

The tight mesh nanocellulose wound dressing reportedly responds to changes in the pH value of the wound, with non-infected wounds demonstrating a pH value of about 5.5 and infected wounds demonstrating a pH value of 8 or higher. This is due to bacteria in the wound changing their surroundings to accommodate their optimal growth environment.

To enable this, the researchers created the dressing using bromthymol blue (BTB), a dye that shifts from yellow to blue when the pH value exceeds 7.

To make the dye suitable for wound dressing applications, it was loaded onto silica featuring nanometer sized pores, which was then combined with the dressing.

Because the wound dressing will change color once pH values of the wound exceed 7, wearers will potentially be alerted to infection long before the visible signs of infection — pus, redness and soreness — appear.

The dressing is detailed in the article, “Nanocellulose composite wound dressings for real-time pH wound monitoring,” which appears in the journal Materials Today Bio.