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

2021 ◽  
Author(s):  
Varun Dwivedi ◽  
Jun-Gyu Park ◽  
Stephen Grenon ◽  
Nicholas Medendorp ◽  
Cory Hallam ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Light Emitting Diode ◽  
Plaque Assay ◽  
Light Emitting ◽  
Novel Device ◽  
Glass Slides ◽  
Ultraviolet C ◽  
Robotic Testing ◽  
Uvc Radiation ◽  
Viral Titers

AbstractEfforts 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.

Effects of ultraviolet-C light-emitting diodes at 275 nm on inactivation of Alicyclobacillusacidoterrestris vegetative cells and its spores as well as the quality attributes of orange juice

2020 ◽  
pp. 108201322095752 ◽  
Author(s):  
Yafei Zhai ◽  
Jiali Tian ◽  
Ruonan Ping ◽  
Hongxia Xiu ◽  
Qisen Xiang ◽  
...  
Keyword(s):  
Orange Juice ◽  
Light Emitting Diodes ◽  
Light Emitting Diode ◽  
Titratable Acidity ◽  
Quality Attributes ◽  
Soluble Solids ◽  
Total Phenolic ◽  
Vegetative Cells ◽  
Light Emitting ◽  
Ultraviolet C

Alicyclobacillus acidoterrestris is a thermoacidophilic, spore-forming bacillus. A. acidoterrestris and its spores can survive in pasteurized juices and cause microbial spoilage. In this work, the effects of ultraviolet-C light-emitting diodes at 275 nm on the inactivation of A. acidoterrestris vegetative cells and its spores in commercial pasteurized orange juice were studied. Meanwhile, the effects of ultraviolet-C light-emitting diodes on the quality attributes of the orange juice were also investigated. The quantities of A. acidoterrestris vegetative cells and its spores inoculated in orange juice were reduced by 6.04 and 2.49 log10 CFU/mL after ultraviolet-C light-emitting diode treatment at 220 mJ/cm2, respectively. The Weibull and Weibull plus tail models were satisfactorily fitted to estimate the reductions of A. acidoterrestris vegetative cells and its spores in orange juice, respectively. Physicochemical properties (pH, titratable acidity, total soluble solids, and clarity) of orange juice did not change significantly after exposure to ultraviolet-C light-emitting diodes. However, the total phenolic content of orange juice decreased with increasing fluence. In addition, ultraviolet-C light-emitting diode treatment at a higher fluence led to a noticeable color difference. These results indicate that ultraviolet-C light-emitting diode treatment has a potential application in the juice processing industry.

Microcontroller-Based System for Estimate of Calcium in Serum Samples

2010 ◽  
Vol 44 (5) ◽  
pp. 433-439
Author(s):  
Periyaswmy Neelamegam ◽  
Abdul Sheriff Jamaludeen ◽  
Annamalai Ragendran ◽  
Krishanamoorthy Murugrananthan
Keyword(s):  
Calcium Binding ◽  
Limit Of Detection ◽  
Light Emitting Diode ◽  
Red Light ◽  
Control Unit ◽  
Arsenazo Iii ◽  
Serum Samples ◽  
Light Emitting ◽  
Commercial Instrument ◽  
Ph Range

Abstract In this study, a microcontroller-based control unit was designed and constructed for the estimation of serum calcium in blood samples. The proposed optoelectronic instrument used a red light emitting diode (LED) as a light source and photodiode as a sensor. The performance of the system was compared with that of a commercial instrument in measuring calcium ion. The quantitative analysis of calcium in a catalyst using arsenazo III as colorimetric reagent was used to test the device. The calibration curve for calcium binding with arsenazo III was drawn to check the range of linearity, which was between 0.1 to 4.5 mM L−1. The limit of detection (LOD) is 0.05 mM L−1. Absorbance changes over the pH range of 2–12 were determined to optimize the assay, with maximum absorption at pH 9.0. Interferences in absorbance from monovalent (K+ and Na+) and divalent (Mg2+) cations were also studied. The results show that the system works successfully.

An AlGaN Core–Shell Tunnel Junction Nanowire Light-Emitting Diode Operating in the Ultraviolet-C Band

Nano Letters ◽  
2017 ◽  
Vol 17 (2) ◽  
pp. 1212-1218 ◽  
Author(s):  
S. M. Sadaf ◽  
S. Zhao ◽  
Y. Wu ◽  
Y.-H. Ra ◽  
X. Liu ◽  
...  
Keyword(s):  
Tunnel Junction ◽  
Light Emitting Diode ◽  
Core Shell ◽  
Light Emitting ◽  
Ultraviolet C

scholarly journals Effects of Combined Aerosolization with Ultraviolet C Light-Emitting Diode on Enterohemorrhagic Escherichia coli and Staphylococcus aureus Attached to Soft Fresh Produce

Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1834
Author(s):  
Chae-Lim Lee ◽  
Geun-Hyang Kim ◽  
Ki-Sun Yoon
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Light Emitting Diode ◽  
Fresh Produce ◽  
Combined Treatment ◽  
Enterohemorrhagic Escherichia Coli ◽  
Light Emitting ◽  
Ultraviolet C ◽  
And Staphylococcus Aureus ◽  
Led Irradiation

Washing soft fresh produce such as strawberries, baby leaves, and sliced onions with sanitizing agents is challenging due to their fragile texture. Thus, treatments like aerosolization using slightly acidic electrolyzed water (SAEW) and ultraviolet C light-emitting diode (UVC LED) irradiation may be good alternatives. In the present study, the reduction effects of a combined treatment of aerosolization using SAEW and UVC LED irradiation on enterohemorrhagic Escherichia coli (EHEC) and Staphylococcus aureus attached to strawberries, baby leaves, and sliced onions were investigated. The behaviours of EHEC and S. aureus, moisture loss, colour measurement, and visual appearance were also analyzed at 10 and 15 °C for 7 days. The reduction effect of the combined treatment with 100 SAEW and UVC LED was higher (0.53–0.92 log CFU g−1) than a single aerosolization treatment (0.11–0.41 log CFU g−1), regardless of samples or pathogens. A greater effect on EHEC and S. aureus reduction was observed in strawberries (0.74 and 0.92 log CFU g−1) than in baby leaves (0.62 and 0.53 log CFU g−1) and sliced onions (0.55 and 0.62 log CFU g−1). The combined treatment further reduced the EHEC and S. aureus populations in strawberries during 7 days of storage at 10 and 15 °C. However, the EHEC and S. aureus populations were maintained in baby leaves and sliced onions at 10 °C for 7 days. Additionally, the greatest effect on the maintenance of colour and appearance was obtained in the combined treatment. Since the combined treatment reduces EHEC and S. aureus populations and preserves visual quality, it could be expected to extend the shelf life of soft fresh produce at the retailer stage of the supply chain.

scholarly journals A Flexible Blue Light-Emitting Diode Based on ZnO Nanowire/Polyaniline Heterojunctions

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Y. Y. Liu ◽  
X. Y. Wang ◽  
Y. Cao ◽  
X. D. Chen ◽  
S. F. Xie ◽  
...  
Keyword(s):  
Blue Light ◽  
Indium Tin Oxide ◽  
Light Emission ◽  
Light Emitting Diode ◽  
Blue Light Emission ◽  
Light Emitting ◽  
Novel Device ◽  
Vertically Aligned ◽  
Doped Polyaniline ◽  
P Type

An organic/inorganic light-emitting diode (LED) consisting of n-type vertically aligned ZnO nanowires (NWs) and p-type proton acid doped polyaniline (PANi) is reported. The device was fabricated on flexible indium-tin-oxide (ITO) coated polyethylene terephthalate (PET) substrate. A broad blue light emission band ranging from 390 nm to 450 nm was observed in the electroluminescence (EL) spectra of the device, which was related to the interface recombination of electrons in the conduction band of ZnO NWs and holes in the polaron level of PANi. The turn-on voltage of the device is~3.5 V, lower than most of ZnO NWs based LED devices. In combination with the easy fabrication, flexibility, low power consumption, and mechanical robustness, this novel device is very promising in the application of blue LEDs.

scholarly journals Practical considerations for Ultraviolet-C radiation mediated decontamination of N95 respirator against SARS-CoV-2 virus

2020 ◽  
Author(s):  
Guillaume R. Golovkine ◽  
Allison W. Roberts ◽  
Chase Cooper ◽  
Sebastian Riano ◽  
Angela M. DiCiccio ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Model Material ◽  
Efficacy Data ◽  
Light Emitting ◽  
Ultraviolet C ◽  
N95 Respirators ◽  
Uv C ◽  
Disinfection Chamber

AbstractDecontaminating N95 respirators for reuse could mitigate shortages during the COVID-19 pandemic. We tested a portable UV-C light-emitting diode disinfection chamber and found that decontamination efficacy depends on mask model, material and location on the mask. This emphasizes the need for caution when interpreting efficacy data of UV-C decontamination methods.

scholarly journals Practical considerations for Ultraviolet-C radiation mediated decontamination of N95 respirator against SARS-CoV-2 virus

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258336
Author(s):  
Guillaume R. Golovkine ◽  
Allison W. Roberts ◽  
Chase Cooper ◽  
Sebastian Riano ◽  
Angela M. DiCiccio ◽  
...  
Keyword(s):  
United States ◽  
Light Emitting Diode ◽  
The United States ◽  
Model Material ◽  
Efficacy Data ◽  
Light Emitting ◽  
Ultraviolet C ◽  
N95 Respirators ◽  
Uv C ◽  
Disinfection Chamber

Decontaminating N95 respirators for reuse could mitigate shortages during the COVID-19 pandemic. Although the United States Center for Disease Control has identified Ultraviolet-C irradiation as one of the most promising methods for N95 decontamination, very few studies have evaluated the efficacy of Ultraviolet-C for SARS-CoV-2 inactivation. In addition, most decontamination studies are performed using mask coupons that do not recapitulate the complexity of whole masks. We sought to directly evaluate the efficacy of Ultraviolet-C mediated inactivation of SARS-CoV-2 on N95 respirators. To that end we created a portable UV-C light-emitting diode disinfection chamber and tested decontamination of SARS-CoV-2 at different sites on two models of N95 respirator. We found that decontamination efficacy depends on mask model, material and location of the contamination on the mask. Our results emphasize the need for caution when interpreting efficacy data of UV-C decontamination methods.

Sign in / Sign up

Export Citation Format

Share Document