Johannes Glaab, Neysha Lobo-Ploch, Hyun Kyong Cho, Thomas Filler, Heiko Gundlach, Martin Guttmann, Sylvia Hagedorn, Silke B. Lohan, Frank Mehnke, Johannes Schleusener, Claudia Sicher, Luca Sulmoni, Tim Wernicke, Lucas Wittenbecher, Ulrike Woggon, Paula Zwicker, Axel Kramer, Martina C. Meinke, Michael Kneissl, Markus Weyers, Ulrike Winterwerber & Sven Einfeldt
Abstract
Multiresistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) cause serious postoperative infections. A skin tolerant far-UVC (< 240 nm) irradiation system for their inactivation is presented here. It uses UVC LEDs in combination with a spectral filter and provides a peak wavelength of 233 nm, with a full width at half maximum of 12 nm, and an irradiance of 44 µW/cm2. MRSA bacteria in different concentrations on blood agar plates were inactivated with irradiation doses in the range of 15–40 mJ/cm2. Porcine skin irradiated with a dose of 40 mJ/cm2 at 233 nm showed only 3.7% CPD and 2.3% 6-4PP DNA damage. Corresponding irradiation at 254 nm caused 15–30 times higher damage. Thus, the skin damage caused by the disinfectant doses is so small that it can be expected to be compensated by the skin’s natural repair mechanisms. LED-based far-UVC lamps could therefore soon be used in everyday clinical practice to eradicate multiresistant pathogens directly on humans.
