Germicidal potential and skin compatibility of an innovative <scp>UVC</scp> phototherapy device emitting at 234 nm

Chronic wounds are a major healthcare issue affecting more than 10 million Americans each year, with a 5-year survival similar to cancer and costing the healthcare system billions of dollars annually. Current solutions, such as antiseptics and antibiotics, can be toxic to cells or contribute to the development of antibiotic-resistant strains of bacteria. Exposure to germicidal ultraviolet radiation (GUV) at 254 nm has been reported as an effective method for chronic wound management. However, concerns about the health hazards from exposure to 254 nm radiation have limited its use for wound management applications. In contrast, wavelengths of ultraviolet radiation in the range of 200-235 nm have exhibited similar germicidal ability but with a lower penetration range in tissue, potentially making those wavelengths better suited for chronic wound disinfection. In this study, a novel phototherapy device emitting principally at 234 nm was used to assess the killing efficacy against Methicillin-resistant Staphylococcus aureus (MRSA). Potential health hazards from exposure using the device were evaluated using a 3D human skin model. The ultraviolet exposure device tested in this study shows promise for effective decontamination of chronic nonhealing wounds without associated health hazards.