Intelligent dressings indicate if wounds have become infected

Scientists at the Fraunhofer Research Institution for Modular Solid State Technologies (EMFT) in Munich have developed dressing materials and plasters that indicate if the wound they are protecting has become infected. If an infection is present, the colour of the dressing changes from yellow to purple. The researchers are now looking for an industrial partner to produce the dressings commercially.

“We have developed an indicator dye which reacts to different pH values, and we have integrated it into a dressing and a plaster,” said researcher Sabine Trupp. Healthy skin and healed wounds have a pH value of below 5. If the pH value is between 6.5 and 8.5 an infection is likely to be present, and the colour of the indicator strip turns from yellow to purple.

The intelligent dressing material will make it possible to regularly check wounds without removing the dressing and disrupting the healing process.

A prototype of the dressing has been produced and initial tests have proved successful. The researchers are now thinking of integrating optical sensors into the dressing to measure the pH value and display the results on a handheld reader. There are also plans to test the dressing in a hospital environment at the University of Regensburg’s dermatology clinic.