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bioRxiv · 10.1101/2021.04.20.440654

Rapid and Efficient Inactivation of SARS-CoV-2 from Surfaces using UVC Light Emitting Diode Device

Abstract

Efforts are underway to develop countermeasures to prevent the environmental spread of COVID-19 pandemic caused by SARS-CoV-2. Physical decontamination methods like Ultraviolet radiation has shown to be promising. Here, we describe a novel device emitting ultraviolet C radiation (UVC), called NuvaWave, to rapidly and efficiently inactivate SARS-CoV-2. SARS-CoV-2 was dried on a chambered glass slides and introduced in a NuvaWave robotic testing unit. The robot simulated waving NuvaWave over the virus at a pre-determined UVC radiation dose of 1, 2, 4 and 8 seconds. Post-UVC exposure, virus was recovered and titered by plaque assay in Vero E6 cells. We observed that relative control (no UVC exposure), exposure of the virus to UVC for one or two seconds resulted in a >2.9 and 3.8 log10 reduction in viral titers, respectively. Exposure of the virus to UVC for four or eight seconds resulted in a reduction of greater than 4.7-log10 reduction in viral titers. The NuvaWave device inactivates SARS-CoV-2 on surfaces to below the limit of detection within one to four seconds of UVC irradiation. This device can be deployed to rapidly disinfect surfaces from SARS-CoV-2, and to assist in mitigating its spread in a variety of settings.

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BibTeXRIS

Dwivedi, V., Park, J.-G., Grenon, S., Medendorp, N., Hallam, C., Torrelles, J. B., Martinez-Sobrido, L., Kulkarni, V.. 2021-04-21. Rapid and Efficient Inactivation of SARS-CoV-2 from Surfaces using UVC Light Emitting Diode Device. https://doi.org/10.1101/2021.04.20.440654

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