scholarly journals Rapid inactivation of SARS-CoV-2 with Deep-UV LED irradiation

2020 ◽  
Author(s):  
Hiroko Inagaki ◽  
Akatsuki Saito ◽  
Hironobu Sugiyama ◽  
Tamaki Okabayashi ◽  
Shouichi Fujimoto
Keyword(s):  
Light Emitting Diode ◽  
Light Emitting ◽  
Uv Led ◽  
Duv Led ◽  
Contact Transmission ◽  
Deep Ultraviolet ◽  
Novel Coronavirus ◽  
And Control ◽  
Led Irradiation

AbstractThe spread of novel coronavirus disease 2019 (COVID-19) infections worldwide has raised concerns about the prevention and control of SARS-CoV-2. Devices that rapidly inactivate viruses can reduce the chance of infection through aerosols and contact transmission. This in vitro study demonstrated that irradiation with a deep ultraviolet light-emitting diode (DUV-LED) of 280 ±5 nm wavelength rapidly inactivates SARS-CoV-2 obtained from a COVID-19 patient. Development of devices equipped with DUV-LED is expected to prevent virus invasion through the air and after touching contaminated objects.

scholarly journals Rapid Inactivation of SARS-CoV-2 Variants by Continuous and Intermittent Irradiation with a Deep-Ultraviolet Light-Emitting Diode (DUV-LED) Device

Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 754
Author(s):  
Hiroko Inagaki ◽  
Akatsuki Saito ◽  
Chiho Kaneko ◽  
Hironobu Sugiyama ◽  
Tamaki Okabayashi ◽  
...  
Keyword(s):  
Ultraviolet Light ◽  
Protective Efficacy ◽  
Light Emitting Diode ◽  
Continuous Irradiation ◽  
Light Emitting ◽  
Antiviral Efficacy ◽  
Duv Led ◽  
Deep Ultraviolet ◽  
Intermittent Irradiation ◽  
Led Irradiation

More than 1 year has passed since social activities have been restricted due to the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More recently, novel SARS-CoV-2 variants have been spreading around the world, and there is growing concern that they may have higher transmissibility and that the protective efficacy of vaccines may be weaker against them. Immediate measures are needed to reduce human exposure to the virus. In this study, the antiviral efficacy of deep-ultraviolet light-emitting diode (DUV-LED) irradiation (280 ± 5 nm, 3.75 mW/cm2) against three SARS-CoV-2 variants was evaluated. For the B.1.1.7, B.1.351, and P.1 variant strains, irradiation of the virus stocks for 1 s resulted in infectious titer reduction rates of 96.3%, 94.6%, and 91.9%, respectively, and with irradiation for 5 s, the rates increased to 99.9%, 99.9%, and 99.8%, respectively. We also tested the effect of pulsed DUV-LED irradiation (7.5 mW/cm2, duty rate: 50%, frequency: 1 kHz) under the same output conditions as for continuous irradiation and found that the antiviral efficacy of pulsed and continuous irradiation was the same. These findings suggest that by further developing and optimizing the DUV-LED device to increase its output, it may be possible to instantly inactivate SARS-CoV-2 with DUV-LED irradiation.

scholarly journals Rapid inactivation of SARS-CoV-2 variants by continuous and intermittent irradiation with a deep-ultraviolet light-emitting diode (DUV-LED) device

2021 ◽  
Author(s):  
Hiroko Inagaki ◽  
Akatsuki Saito ◽  
Chiho Kaneko ◽  
Hironobu Sugiyama ◽  
Tamaki Okabayashi ◽  
...  
Keyword(s):  
Ultraviolet Light ◽  
Protective Efficacy ◽  
Light Emitting Diode ◽  
Continuous Irradiation ◽  
Light Emitting ◽  
Antiviral Efficacy ◽  
Duv Led ◽  
Deep Ultraviolet ◽  
Intermittent Irradiation ◽  
Led Irradiation

More than 1 year has passed since social activities have been restricted due to the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More recently, novel SARS-CoV-2 variants have been spreading around the world, and there is growing concern of higher transmissibility of the variants and weaker protective efficacy of vaccine against the variants. Immediate measures are needed to reduce human exposure to the virus. In this study, the antiviral efficacy of deep-ultraviolet light-emitting diode (DUV-LED) irradiation (280 ± 5 nm, 3.75 mW/cm2) against three SARS-CoV-2 variants was evaluated. For the B.1.1.7, B.1.351, and P.1 strains, the infectious titer reduction rates of 96.3%, 94.6%, and 91.9%, respectively, were already recognized with the irradiation of virus stocks for 1 s, and the rates increased to 99.9%, 99.9%, and 99.8%, respectively, with irradiation for 5 s. We also tested the effect of pulsed DUV-LED irradiation (7.5 mW/cm2, duty rate: 50%, frequency: 1 KHz) under the same output conditions as continuous irradiation, and found that the antiviral efficacy of pulsed and continuous irradiation was the same. These findings suggest that SARS-CoV-2 may be instantly inactivated by DUV-LED irradiation if the DUV-LED device is further developed and optimized to increase its output.

scholarly journals Some Measures for COVID-19 Including Deep Ultraviolet Light-Emitting Diode (DUV-LED), Gc protein-derived Macrophage-Activating Factor (Gcmaf), and 5-Aminolevulinic Acid (5-ALA)

2021 ◽  
Vol 4 (2) ◽  
pp. 110-113
Author(s):  
Hiroshi Bando
Keyword(s):  
Influenza A ◽  
Aminolevulinic Acid ◽  
Light Emitting Diode ◽  
Protoporphyrin Ix ◽  
Chronic Fatigue ◽  
Influenza A Viruses ◽  
Light Emitting ◽  
Duv Led ◽  
Deep Ultraviolet ◽  
Gc Protein

Several trials for the COVID-19 pandemic are found. Prof. Shunji Nakamura, Tokushima University was awarded the 2014 Nobel prize in Physics for light-emitting diodes (LEDs). Deep ultraviolet LED (DUV-LED) causes SARS-CoV-2 inactivation as 99.9% by 265 nm. Gc protein-derived macrophage-activating factor (GcMAF)-based immunotherapy has a wider application for serious infection, chronic fatigue syndrome, and cancers. Covid center in Naples submitted a phase II report concerning GcMAF and COVID-19 in Feb 2021. 5-aminolevulinic acid (5-ALA) and its metabolite protoporphyrin IX (PpIX) show anti-inflammatory and antiviral effects for Zika, Dengue, influenza A viruses, and SARS-CoV-2. These results hopefully contribute to the research development for COVID-19.

scholarly journals Deep Ultraviolet Light-Emitting Diode Light Therapy for Fusobacterium nucleatum

2021 ◽  
Vol 9 (2) ◽  
pp. 430
Author(s):  
Soichiro Fukuda ◽  
Shunsuke Ito ◽  
Jun Nishikawa ◽  
Tatsuya Takagi ◽  
Naoto Kubota ◽  
...  
Keyword(s):  
Dna Damage ◽  
Light Emitting Diode ◽  
Fusobacterium Nucleatum ◽  
Light Therapy ◽  
Bactericidal Effect ◽  
Light Emitting ◽  
Led Light ◽  
Pyrimidine Dimers ◽  
Duv Led ◽  
Deep Ultraviolet

Background: Fusobacterium nucleatum, which is associated with periodontitis and gingivitis, has been detected in colorectal cancer (CRC). Methods: We evaluated the bactericidal effect of deep ultraviolet (DUV) light-emitting diode (LED) light therapy on F. nucleatum both qualitatively and quantitatively. Two DUV-LEDs with peak wavelengths of 265 and 280-nm were used. DNA damage to F. nucleatum was evaluated by the production of cyclobutane pyrimidine dimers (CPD) and pyrimidine (6–4) pyrimidone photoproducts (6–4PP). Results: DUV-LEDs showed a bactericidal effect on F. nucleatum. No colony growth was observed after 3 min of either 265 nm or 280 nm DUV-LED irradiation. The survival rates of F. nucleatum under 265 nm DUV-LED light irradiation dropped to 0.0014% for 10 s and to 0% for 20 s irradiation. Similarly, the survival rate of F. nucleatum under 280 nm DUV-LED light irradiation dropped to 0.00044% for 10 s and 0% for 20 s irradiation. The irradiance at the distance of 35 mm from the DUV-LED was 0.265 mW/cm2 for the 265 nm LED and 0.415 mW/cm2 for the 280 nm LED. Thus, the radiant energy for lethality was 5.3 mJ/cm2 for the 265 nm LED and 8.3 mJ/cm2 for the 280 nm LED. Amounts of CPD and 6–4PP in F. nucleatum irradiated with 265 nm DUV-LED light were 6.548 ng/µg and 1.333 ng/µg, respectively. Conclusions: DUV-LED light exerted a bactericidal effect on F. nucleatum by causing the formation of pyrimidine dimers indicative of DNA damage. Thus, DUV-LED light therapy may have the potential to prevent CRC.

scholarly journals Quantitative evaluation of SARS-CoV-2 inactivation using a deep ultraviolet light-emitting diode

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Takeo Minamikawa ◽  
Takaaki Koma ◽  
Akihiro Suzuki ◽  
Takahiko Mizuno ◽  
Kentaro Nagamatsu ◽  
...  
Keyword(s):  
Ultraviolet Light ◽  
Irradiation Dose ◽  
Light Emitting Diode ◽  
Biological Effects ◽  
Basic Knowledge ◽  
Light Emitting ◽  
Antiviral Effects ◽  
Critical Measure ◽  
Duv Led ◽  
Deep Ultraviolet

AbstractInactivation technology for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is certainly a critical measure to mitigate the spread of coronavirus disease 2019 (COVID-19). A deep ultraviolet light-emitting diode (DUV-LED) would be a promising candidate to inactivate SARS-CoV-2, based on the well-known antiviral effects of DUV on microorganisms and viruses. However, due to variations in the inactivation effects across different viruses, quantitative evaluations of the inactivation profile of SARS-CoV-2 by DUV-LED irradiation need to be performed. In the present study, we quantify the irradiation dose of DUV-LED necessary to inactivate SARS-CoV-2. For this purpose, we determined the culture media suitable for the irradiation of SARS-CoV-2 and optimized the irradiation apparatus using commercially available DUV-LEDs that operate at a center wavelength of 265, 280, or 300 nm. Under these conditions, we successfully analyzed the relationship between SARS-CoV-2 infectivity and the irradiation dose of the DUV-LEDs at each wavelength without irrelevant biological effects. In conclusion, total doses of 1.8 mJ/cm2 for 265 nm, 3.0 mJ/cm2 for 280 nm, and 23 mJ/cm2 for 300 nm are required to inactivate 99.9% of SARS-CoV-2. Our results provide quantitative antiviral effects of DUV irradiation on SARS-CoV-2, serving as basic knowledge of inactivation technologies against SARS-CoV-2.

scholarly journals Quantitative Evaluation of SARS-CoV-2 Inactivation Using a Deep Ultraviolet Light-Emitting Diode

2020 ◽  
Author(s):  
Takeo Minamikawa ◽  
Takaaki Koma ◽  
Akihiro Suzuki ◽  
Takahiko Mizuno ◽  
Kentaro Nagamatsu ◽  
...  
Keyword(s):  
Ultraviolet Light ◽  
Irradiation Dose ◽  
Light Emitting Diode ◽  
Biological Effects ◽  
Basic Knowledge ◽  
Light Emitting ◽  
Antiviral Effects ◽  
Critical Measure ◽  
Duv Led ◽  
Deep Ultraviolet

Abstract Inactivation technology for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is certainly a critical measure to mitigate the spread of coronavirus disease 2019 (COVID-19). A deep ultraviolet light-emitting diode (DUV-LED) would be a promising candidate to inactivate SARS-CoV-2, based on the well-known antiviral effects of DUV on microorganisms and viruses. However, due to variations in the inactivation effects across different viruses, quantitative evaluations of the inactivation profile of SARS-CoV-2 by DUV-LED irradiation need to be performed. In the present study, we quantify the irradiation dose of DUV-LED necessary to inactivate SARS-CoV-2. For this purpose, we determined the culture media suitable for the irradiation of SARS-CoV-2 and optimized the irradiation apparatus using commercially available DUV-LEDs that operate at a center wavelength of 265, 280, or 300 nm. Under these conditions, we successfully analyzed the relationship between SARS-CoV-2 infectivity and the irradiation dose of the DUV-LEDs at each wavelength without irrelevant biological effects. In conclusion, total doses of 1.8 mJ/cm2 for 265 nm, 3.0 mJ/cm2 for 280 nm, and 23 mJ/cm2 for 300 nm are required to inactivate 99.9% of SARS-CoV-2. Our results provide quantitative antiviral effects of DUV irradiation on SARS-CoV-2, serving as basic knowledge of inactivation technologies against SARS-CoV-2.

scholarly journals Light-emitting diode exposure enhances sperm motility in men with and without asthenospermia: preliminary results

2015 ◽  
Vol 87 (1) ◽  
pp. 14 ◽  
Author(s):  
Nader Salama ◽  
Mohamed El-Sawy
Keyword(s):  
Sperm Motility ◽  
Intrauterine Insemination ◽  
Light Emitting Diode ◽  
Blue Staining ◽  
Time Interval ◽  
Time Intervals ◽  
Light Emitting ◽  
Red Led ◽  
And Control

Objective: To evaluate the effect of lightemitting diode (LED) on sperm motility in men with and without asthenospermia. Material and Methods: Semen samples from 27 men were assessed and washed. An aliquot was taken from each sample as a control. The remaining amount was exposed to red LED for 2, 5 and 10 minutes. Sperm motility from the test and control tubes were re-checked at the end of each time interval. In 11 of these 27 samples, the same protocol was repeated without sperm washing. Evaluation of sperm creatine kinase (CK) activity, hypoosmotic swelling (HOS) test and aniline blue staining (ANBS) were undertaken after phototherapy in additional 15 samples. Results: Progressive sperm motility increased significantly after LED treatment at the different time intervals whether in washed (p = 0.000) or non-washed (p = 0.003) samples. The amount of the increase in motility in washed aliquots was significantly more (p = 0.000) than in naive semen. Sperm CK activity increased, but was not significant whilst there were no changes regarding HOS and ANBS. Conclusion: Red LED is a promising safe tool to boost sperm motility in vitro. This may have a great implication on maximizing the possibilities and outcomes of intrauterine insemination trials.

Progress and Perspective of Near-Ultraviolet and Deep-Ultraviolet Light-Emitting Diode Packaging Technologies

2019 ◽  
Vol 141 (4) ◽  
Author(s):  
Yang Peng ◽  
Renli Liang ◽  
Yun Mou ◽  
Jiangnan Dai ◽  
Mingxiang Chen ◽  
...  
Keyword(s):  
Ultraviolet Light ◽  
Light Emitting Diodes ◽  
Light Emitting ◽  
Near Ultraviolet ◽  
Uv Led ◽  
Duv Led ◽  
Deep Ultraviolet ◽  
Uv Leds ◽  
Ultraviolet Light Emitting Diodes ◽  
Light Efficiency

Abstract Ultraviolet light-emitting diodes (UV-LEDs) have drawn considerable attention in environment, life science, and industry fields, such as the applications of near UV-LEDs in resin curing, illumination, and identification, and deep UV-LEDs in disinfection, medical treatment, and biochemical inspection. However, due to the limitation of packaging technology, UV-LED devices exhibit low light efficiency and poor reliability compared with visible LEDs. The organic encapsulation materials are prone to UV aging, thermal degradation, and nonairtightness, which significantly reduce the performances of UV-LEDs. In order to solve this issue, UV-LED packaging technology has been proposed for UV-LED devices instead of conventional LED packaging. In this review, we investigated in detail the overview and challenges of near-ultraviolet light-emitting diodes (NUV-LED)/deep-ultraviolet light-emitting diodes (DUV-LED) packaging. For the packaging of UV-LEDs, all inorganic encapsulation materials, hermetic packaging structures with low-temperature bonding, reduced reflection losses, UV stable and transparent materials, and effective thermal management are key progresses to enhance the light efficiency and reliability of UV-LEDs. In addition, the summary and perspectives of NUV-LED/DUV-LED packaging were introduced and discussed.

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