At Fraunhofer IKTS, innovative dressings are electrospun from polylactic acid (PLA), a polymer that breaks down in the body. Specially incorporated active ingredients provide long-term improvements in wound healing and effectively prevent wound infection.

Roughly one million people in Germany are receiving treatment for chronic wounds caused by conditions ranging from circulatory disorders and pressure ulcers to diabetes-related foot problems. Treatment costs total some 7.5 billion euros annually, and patients endure considerable suffering. Researchers at Fraunhofer IKTS in Dresden are developing a natural treatment with minimal side effects that could help address antibiotic resistance and ease patients’ suffering.

Fraunhofer IKTS research scientist Peter Schmieder and his colleagues are developing special dressings for this purpose: “Unlike conventional dressings, the white material in our dressings contains active ingredients,” he explains. “This gives them antimicrobial properties that can help wounds heal.”

The researchers make the dressings from electrospun membranes. Although electrospinning dates back about 100 years, it has recently been revived and refined. A polymer solution is loaded into a syringe and ejected into an electric field, where it deposits fine fibers. Repeating this process long enough creates a fabric resembling a handkerchief that serves as the basis for the new dressings.

Previous approaches focused on individual factors involved in wound healing. Now, for the first time, researchers are incorporating several active ingredients into the dressing membranes: antibacterial bacteriophages, proteins that promote wound healing and antiseptic nanomaterials known as MXenes.

Partners in the AntiMicroMXen project, which is funded by the M-ERA.NET consortium, first culture these components in the lab or recover them from hospital wastewater. Each serves a different purpose: “Bacteriophages kill bacteria, making bacteriophages a natural alternative to antibiotics. The incorporated proteins promote the growth of new skin cells, accelerating wound closure,” explains Schmieder. “MXenes have antiseptic properties that help fight pathogens in the wound.”

The active ingredients embedded in the membrane must meet a wide range of requirements, posing a particular challenge. For example, bacteriophages and proteins are sensitive and must be protected from ambient factors such as pH and temperature to remain effective. The researchers therefore need to pack these two components into the membrane fibers as densely as possible. MXenes, by contrast, are most effective at killing pathogens when irradiated and heated. They must therefore be positioned as close as possible to the membrane’s outer surface.

Peter Schmieder and the team from the Biofunctional Materials and Point-of-Care Diagnostics group are currently incorporating each active ingredient separately and testing its activity before combining them all. According to Schmieder, electrospinning is particularly well suited to incorporating biological components because it does not require high temperatures, leaving protein structures intact. However, because the process uses high voltage, the project partners must check to ensure that the biomaterials survived the manufacturing process intact.

In addition to use in wound dressings, these active agents could be incorporated into food packaging to protect food from foodborne pathogens such as Salmonella, says Schmieder. The new wound dressings are among the many medical applications being studied by Fraunhofer IKTS in its Bio- and Medical Technology business unit. Development of the materials and integration of the active ingredients are expected to be completed by May 2027. Interested clinical partners are invited to participate in testing to support regulatory approval of the new materials.

AntiMicroMXen project

Objective: The project titled Electrospun scaffolds with antimicrobial and wound-healing capabilities utilizing bacteriophages, mesenchymal stem cell-derived factors and MXenes, or AntiMicroMXen for short, incorporates antibacterial bacteriophages, antiseptic MXenes and growth factors that promote wound healing into an electrospun membrane. The resulting dressings release these active ingredients directly at the wound site. They are designed to provide lasting improvements in wound healing compared with conventional treatments and effectively prevent wound infection.

Project partners:
-    Fraunhofer Institute for Ceramic Technologies and Systems IKTS (coordinator)
-    Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy
     of Sciences
-    University of Latvia
-    NanoCarbonTech, Poland

Project duration: June 2024 to May 2027

Project funded by: Sächsische Aufbaubank, Saxon State Ministry for Science, Culture and Tourism, M-ERA.NET; co-funded by the European Union