Ultraviolet disinfection efficacy test method using bacteria monolayers.

Autor: Kowalski W; Sanuvox, Montreal, Quebec, Canada. Electronic address: wkowalski@sanuvox.com., Moeller R; German Aerospace Center (DLR e.V.), Institute of Aerospace Medicine, Radiation Biology Department, Aerospace Microbiology Research Group, Cologne, Germany., Walsh TJ; Infectious Diseases Translational Research Laboratory, Transplantation-Oncology Infectious Diseases Program, Weill Cornell Medicine of Cornell University, New York City, NY, USA., Petraitis V; Infectious Diseases Translational Research Laboratory, Transplantation-Oncology Infectious Diseases Program, Weill Cornell Medicine of Cornell University, New York City, NY, USA., Passman FJ; Biodeterioration Control Associates, Inc., Princeton, NJ, USA.
Jazyk: angličtina
Zdroj: Journal of microbiological methods [J Microbiol Methods] 2022 Sep; Vol. 200, pp. 106541. Date of Electronic Publication: 2022 Jul 21.
DOI: 10.1016/j.mimet.2022.106541
Abstrakt: Monolayers of bacterial cells of Staphylococcus aureus and Pseudomonas aeruginosa were inoculated on glass slide carriers using an automated inoculum spray deposition system. The use of bacterial monolayers allows for control of critical variables for testing and verification of light-based disinfection technologies. This approach avoids the variability associated with manual inoculation and high inoculum titers, which can engender clustering of cells and the associated photoprotection that clustering incurs. The use of glass slide carriers avoids problems caused by irregular microscopic surface features, which can impact the efficacy evaluation of light-based disinfection technologies. Scanning electron micrographic (SEM) imaging was used to verify the surface topography and the presence of monolayers. The spray deposition method produced a mean density of >10 6 colony forming units (CFU) per carrier. The inoculated carriers were exposed to ultraviolet light for 120 s from a focused multivector ultraviolet (FMUV) light system. A mean log CFU reduction of 4.8 was achieved for S. aureus (p < 0.0001). A mean log CFU reduction of 5.1 was achieved for P. aeruginosa (p < 0.0001). The test method presented herein will facilitate increased accuracy in the measurement of ultraviolet susceptibility rate constants.
Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare.
(Copyright © 2022 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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