Department of Biomedical Engineering, Binghamton University, State University of New York (SUNY), PO Box 6000, Binghamton, NY, 13902, USA.
Center of Biomanufacturing for Regenerative Medicine, Binghamton University, State University of New York (SUNY), Binghamton, NY, 13902, USA.
Sci Rep. 2022 Apr 7;12(1):5869. doi: 10.1038/s41598-022-09930-2.
The ongoing COVID-19 global pandemic has necessitated evaluating various disinfection technologies for reducing viral transmission in public settings. Ultraviolet (UV) radiation can inactivate pathogens and viruses but more insight is needed into the performance of different UV wavelengths and their applications. We observed greater than a 3-log reduction of SARS-CoV-2 infectivity with a dose of 12.5 mJ/cm of 254 nm UV light when the viruses were suspended in PBS, while a dose of 25 mJ/cm was necessary to achieve a similar reduction when they were in an EMEM culture medium containing 2%(v/v) FBS, highlighting the critical effect of media in which the virus is suspended, given that SARS-CoV-2 is always aerosolized when airborne or deposited on a surface. It was found that SARS-CoV-2 susceptibility (a measure of the effectiveness of the UV light) in a buffer such as PBS was 4.4-fold greater than that in a cell culture medium. Furthermore, we discovered the attenuation of UVC disinfection by amino acids, vitamins, and niacinamide, highlighting the importance of determining UVC dosages under a condition close to aerosols that wrap the viruses. We developed a disinfection model to determine the effect of the environment on UVC effectiveness with three different wavelengths, 222 nm, 254 nm, and 265 nm. An inverse correlation between the liquid absorbance and the viral susceptibility was observed. We found that 222 nm light was most effective at reducing viral infectivity in low absorbing liquids such as PBS, whereas 265 nm light was most effective in high absorbing liquids such as cell culture medium. Viral susceptibility was further decreased in N95 masks with 222 nm light being the most effective. The safety of 222 nm was also studied. We detected changes to the mechanical properties of the stratum corneum of human skins when the 222 nm accumulative exposure exceeded 50 J/cm.The findings highlight the need to evaluate each UV for a given application, as well as limiting the dose to the lowest dose necessary to avoid unnecessary exposure to the public.
持续的 COVID-19 大流行需要评估各种消毒技术，以减少公共场所的病毒传播。紫外线 (UV) 辐射可以使病原体和病毒失活，但需要更多地了解不同 UV 波长的性能及其应用。当病毒悬浮在 PBS 中时，我们观察到用 254nm UV 光照射 12.5mJ/cm 剂量可使 SARS-CoV-2 感染力降低 3 个对数级，而当病毒在含有 2%（v/v）FBS 的 EMEM 培养基中时，需要 25mJ/cm 的剂量才能达到类似的降低效果，这突出了病毒悬浮介质的关键作用，因为 SARS-CoV-2 在空中或在表面上沉积时总是气溶胶化的。研究发现，SARS-CoV-2 在缓冲液（如 PBS）中的易感性（衡量 UV 光的有效性）比在细胞培养基中高 4.4 倍。此外，我们发现氨基酸、维生素和烟酰胺会使 UVC 消毒效果减弱，这突出了在接近包裹病毒的气溶胶的条件下确定 UVC 剂量的重要性。我们开发了一种消毒模型，用三种不同的波长（222nm、254nm 和 265nm）来确定环境对 UVC 效果的影响。观察到液体吸收率与病毒易感性之间呈反比关系。我们发现，222nm 光在低吸收率的液体（如 PBS）中最有效地降低病毒感染力，而 265nm 光在高吸收率的液体（如细胞培养基）中最有效。N95 口罩进一步降低了病毒的易感性，其中 222nm 光的效果最显著。还研究了 222nm 的安全性。当 222nm 的累积暴露量超过 50J/cm 时，我们检测到人体皮肤角质层的机械性能发生了变化。这些发现突出表明需要针对特定应用评估每种 UV，并且将剂量限制在最低必要剂量以避免对公众的不必要暴露。
