ETH team develops hydrogel against resistant wound bacteria

(CONNECT) A team led by ETH Professor Raffaele Mezzenga and researchers from the University of Shanghai have developed a hydrogel that not only combats bacteria in wounds, but also actively promotes wound healing. According to a press release, this water-based gel has reduced the bacterial load by 95 percent in preclinical animal tests. The treated wound closed within 15 days, which was not the case with untreated control wounds. The study was recently published in the journal "Nature Communications".

The hydrogel is applied directly to the wound and remains there during the healing process. It is absorbed into the tissue and slowly degrades itself. In the gel, the researchers have imitated reticular protein structures that release immune cells in order to capture pathogens and render them harmless. "In contrast to many synthetic approaches, we rely on a natural, protein-based system," Mezzenga is quoted as saying.

It consists of a dense network of tiny protein fibers made from the still inactive antibacterial enzyme lysozyme. It is activated by irradiation with near-infrared light. This releases individual lysozyme molecules, which then kill bacteria. The gel also releases magnesium ions under this light. They cause pro-inflammatory immune cells to be reprogrammed into a regenerative cell type. The immune system calms down and the wound heals. When the light is switched off, the gel returns to its net shape.

"Our technology combines antibacterial effect, anti-inflammation and wound healing," says Qize Xuan from the University of Shanghai, explaining the innovation. He is the first author of the study and a former visiting doctoral student in Mezzenga's laboratory. "This could one day open up new possibilities, particularly for diabetic patients with chronic wounds or those with antibiotic resistance." The team is now looking for industrial partners for clinical studies. ce/mm