World's First*¹ Clarification of Part of the Inactivation Mechanism of SARS-CoV-2 by nanoe™
(Hydroxyl Radicals Contained in Water) Technology

Expected to be effective against future SARS-CoV-2 variants

Osaka, Japan – Panasonic Corporation ("Panasonic") today announced that through collaborative research with Associate Professor Mayo Yasugi of the Graduate School of Veterinary Science, Osaka Metropolitan University, it has revealed for the first time that the structural collapse of the SARS-CoV-2 is one of the causes of the inactivation of the viruses through exposure to nanoe™.

nanoe™ is a technology that collects invisible moisture in the air and applies a high voltage to it to produce “hydroxyl radicals contained in water”. Hydroxyl radicals inhibit the growth of pollutants such as bacteria and viruses. They are characterized by being strongly oxidative and highly reactive, hence a short life span. Contained in tiny water particles, nanoe™ has a long lifespan and can spread over long distances. It has an inhibitory effect on both airborne and adhered substances.
Learn more about nanoe :
https://www.panasonic.com/th/nanoe/all/how-nanoe-works/bacteria-viruses.html

The SARS-CoV-2 infection (COVID-19) that occurred in 2019 still shows no signs of convergence due to the emergence of the Omicron strain, a highly infectious mutant virus. The Omicron strain continues to mutate and increase the number of descendant strains (subtypes), and it is conceivable that the number of infected people may increase rapidly due to a specific variant among them. However, the only way to prevent the spread of such infection is to thoroughly implement basic measures such as ventilation, wearing a mask when necessary, washing hands, avoiding the Three Cs (Close-contact settings, Crowded places, Closed spaces), and vaccination.
The company performed several tests and demonstrated the following effects of nanoe™ technology for inhibiting the SARS-CoV-2:
1) Inhibitory effect*² on the SARS-CoV-2 in July 2020;
2) Inhibitory effect*³ on four SARS-CoV-2 variants in November 2021; and
3) Inhibitory effect*⁴ on the SARS-CoV-2 in a test space of approximately 24 m³ in March 2022. In addition, it has been shown that the inoculation of Vero cells*⁵ with the SARS-CoV-2 which had been exposed to nanoe™ does not suffer cell death, suggesting that infection does not occur. However, until now, it has not been clarified how nanoe™ acts on and inactivates the SARS-CoV-2.

Therefore, by focusing on the mechanism of how the SARS-CoV-2 is inactivated by nanoe™, such viruses were tested with and without exposure to nanoe™. The test included measurements of the effects of nanoe™ on each component of the virus and the amount of virus binding to cells. As a result, it was confirmed that nanoe™ acted at multiple steps on the envelope, proteins, and genomic RNA that make up the virus. In addition, it has been suggested that viruses exposed to nanoe™ lose their ability to bind to cells, thereby inhibiting infection. This revealed part of the mechanism by which nanoe™ inactivates the SARS-CoV-2. Please note that the verification results are based on tests in a closed test environment and not in an actual use space.

Panasonic will continue to pursue the potential of nanoe™ technology and contribute to society by providing safe and secure spaces in the future.

■ Methodology and data
・Verification organization: Osaka Metropolitan University
・Subject: SARS-CoV-2
・Equipment to be verified: Generator of nanoe™
・Verification method: In a 45 L test space, a nanoe™ generator was installed 15 cm above the bottom face.
A piece of gauze saturated with the virus solution was placed in a petri dish, and then the gauze was exposed to nanoe™ for the predetermined period of time. Subsequently, the following measurements were carried out: 1) Morphological observation through a transmission electron microscope (Figure 1); 2) Measurement of the amount of protein (Figure 2); 3) Measurement of the amount of genomic RNA (Figure 3); and 4) Measurement of the ability to bind to cells (Figure 5).

・Verification results:

Figure 1 Morphological observation of the SARS-CoV-2 through a transmission electron microscope

1: SARS-CoV-2 sample group not exposed to nanoe™
2: SARS-CoV-2 sample group exposed to nanoe™
Morphological distortion (suggesting damage to the envelope) was observed in the sample group exposed to nanoe™

Figure 2 Electrophoresis of SARS-CoV-2 proteins

A decrease in the amount of proteins was observed in the nanoe™-exposed sample group compared to the one without exposure.
* Stained blue when proteins are present.

Figure 5 Measurement of the ability to bind to cells (measurement of the amount of viral genomic RNA (left panel) and viral proteins (right panels))

Measured the amounts of genomic RNA and viral proteins in a state where viruses were bound to cells
Decreases in both amounts were observed in the sample group exposed to nanoe™.

■ Conclusion
nanoe™ does not target specific molecules or structures of viruses, but damages SARS-CoV-2 by acting at multiple steps on the envelope, proteins, and genomic RNA that make up viruses. Viruses damaged by exposure to nanoe™ lose their ability to bind to host cell receptors, thereby becoming less infectious. These series of phenomena are considered to be part of the mechanism of how the SARS-CoV-2 is inactivated by nanoe™. (Figure 6)

Figure 6 Image of the mechanism of SARS-CoV-2 inactivation

■ Methodology and data
・Verification organization: Japan Textile Products Quality and Technology Center
・Subject: SARS-CoV-2 (Omicron strain BA.5)
・Equipment to be verified: Generator of nanoe™
・Verification method: In a 45 L test space, a nanoe™ generator was installed 15 cm above the bottom face.
A piece of gauze saturated with the virus solution was placed in a petri dish, and then the gauze was exposed to nanoe™ or the predetermined period of time. Subsequently, the infection titer was measured and the spread of infection to cells was observed.

・Verification results:

<Measurement of the infection titer>

<Observation of the spread of infection to cells>
Vero cells^*5 were inoculated with a SARS-CoV-2 that had been exposed to nanoe™ and one without exposure, respectively. After waiting for approximately 7 hours for the conditions of the cells to stabilize, time-lapse imaging was taken with an interval of 10 minutes.

■ Principle of nanoe™ generation
nanoe™, which is approximately 5 to 20 nm in size and contains OH radicals, is generated by cooling the atomizing electrode with a Peltier element; producing water through the condensation of moisture in the air; and applying a high voltage between the atomizing electrode and the counter electrode.

Figure 7 nanoe™ generator

*¹ As ion emission air purification technology (Panasonic data as of June 8, 2022)
*² [Press Release] Verification of inhibitory effect of hydroxyl radicals contained in water (nano-sized electrostatic atomized water particle) on the SARS-CoV-2 (July 2020)
*³ [Press Release] Panasonic Announces Verification of Inhibitory Effect of Hydroxyl Radicals Contained in Water (Nano-Sized Electrostatic Atomized Water Particle) on 4 SARS-CoV-2 Variants (November 2021)
 Since the virus infection titer of the SARS-CoV-2 and the four variants showed the same decreasing trend regardless of the strain, an expert suggested that the nanoe™ technology does not affect the inactivation effect of viral mutations caused by some amino acid substitutions, and that the same results can be expected for variants that may appear in the future if tests are conducted under the same conditions of a 45 L space.
*⁴ [Press Release] World First Verified Inhibitory Effect of Hydroxyl Radicals Contained in Water (Nano-Sized Electrostatic Atomized Water Particle) on Adhered SARS-CoV-2 in a 24 m³ Test Space (March 2022)
*⁵ Host cells used to culture SARS-CoV-2

About Panasonic Corporation
Panasonic Corporation offers products and services for a variety of living environments, ranging from homes to stores to offices and cities. There are five businesses at the core of Panasonic Corporation: Living Appliances and Solutions Company, Heating & Ventilation A/C Company, Cold Chain Solutions Company, Electric Works Company and China and Northeast Asia Company. The operating company reported consolidated net sales of 3,647.6 billion yen for the year ended March 31, 2022. Panasonic Corporation is committed to fulfilling the mission of Life Tech & Ideas: For the wellbeing of people, society and the planet, and embraces the vision of becoming the best partner of your life with human-centric technology and innovation. Learn more about Panasonic: https://www.panasonic.com/global/about/