Wounds heal naturally most of the time. However, sometimes they do develop secondary infections or take longer to heal. Doctors or nurses, who dress the wounds have to take out the dressing, clean, make sure it’s not infected and then redress it. However, this is painful process and is also prone to be the source of infection. Now scientists came up with a dressing material that will indicate if the wound is healing well or is infected without opening the dressing.
The idea sound really simple but very innovative. No complicated nanotechnology etc.
“Healthy skin and healed wounds usually show a pH value of below 5. If this value increases, it is shifting from the acid to the alkaline range, which indicates complications in the healing of the wound. If the pH value is between 6.5 und 8.5 an infection is frequently present and the indicator color strip turns purple,” states Dr. Sabine Trupp, scientist at the EMFT, explaining the chemical reaction. In this way the intelligent dressing material makes it possible to regularly check wounds from the outside without disrupting the healing process.
Production of the color control strip posed a number of challenges for the research scientists as it had to meet several different requirements: “The dye has to remain chemically stable when bonded to the fibers of the dressing material or the plaster to ensure that it does not get into the wound. At the same time, the indicator must show a clear change in color and also react sensitively in the right pH range,” says Trupp. The experts succeeded in meeting all these requirements. A prototype of the dressing has already been produced and initial tests have proved successful. The researchers are now thinking about how to develop their innovation further. There are plans to integrate optical sensor modules into the dressing to measure the pH value and indicate the results on a reader unit. This method would allow the value to be read off precisely, providing information about how the wound is healing.
German scientists at the Fraunhofer Research Institution for Modular Solid State Technologies EMFT in Munich have developed dressing materials and plasters which indicate pathological changes in the skin. If an infection is present, the color of the dressing changes from yellow to purple.