© 2018 Welch et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Drug-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) are a target for new antimicrobial technologies. Far-UVC technology is an emerging disinfection method that directly kills microorganisms using light. In contrast with conventional UV sterilization, far-UVC light has antimicrobial capabilities without apparent harm to mammalian cells. This study examines the application of 224 nm far-UVC light delivered from a laser using an optical diffuser towards the goal of protecting against bacterial invasion around skin penetrating devices. Delivery of far-UVC using a laser and optical fibers enables exposure to unique geometries that would otherwise be shielded when using a lamp. Testing of the bactericidal potential of diffusing the far-UVC laser output over a large area was tested and yielded qualitative area killing results. The killing of MRSA using this method was also examined using an in vitro survival assay. Results followed a classic log-linear disinfection model with a rate constant of k = 0.51 cm2/mJ, which corresponds to an inactivation cross section of D90= 4.5 mJ/cm2. This study establishes far-UVC delivered from a laser through an optical diffuser as a viable solution for disinfection of susceptible regions such as around catheters, drivelines, or other skin penetrating medical devices.
Welch, D., Buonanno, M., Shuryak, I., Randers-Pehrson, G., Spotnitz, H. M., & Brenner, D. J. (2018). Effect of far ultraviolet light emitted from ann optical diffuser on methicillin-resistant Staphylococcus aureus in vitro. PLoS ONE, 13(8). https://doi.org/10.1371/journal.pone.0202275