Dr. Moriya Tsuji, M.D., Ph.D. is a Professor of Medicine in the Division of Infectious Diseases, Department of Medicine at the Columbia University Irving Medical Center, a world-renowned research institute in the United States. Professor Tsuji and his colleagues have demonstrated for the first time in the world a robust antiviral effect exerted by a Plasmacluster technology developed by Sharp Corporation. The research team has found that the exposure of Plasmacluster ions to an airborne virus of a recent coronavirus variant, SARS-CoV-2 Omicron BA.1 for only 15 minutes resulted in reducing the virus infectious titer*3 by 99.3%.

In this airborne virus study, a highly concentrated solution of the Omicron BA.1 variant, a mutated strain of the novel coronavirus (SARS-CoV-2), was sprayed into a 102L test box*4 in the form of an aerosol followed by releasing Plasmacluster ions (ion density approximately 25,000 pcs/cm3) to verify the effectiveness of reducing airborne virus. The results showed a drastic reduction of the virus infectious titer (99.3% reduction after 15 minutes of exposure), indicating that Plasmacluster technology is vastly effective against mutated and highly infectious airborne Omicron variant.

This study was initiated in April 2020 by an inquiry about Sharp Plasmacluster technology from Columbia University, who was investigating effective infection control technology against the novel coronavirus (SARS-CoV-2). At that time, the number of infected people and deaths had rapidly increased worldwide from the initial onset of the novel coronavirus disease (COVID-19) outbreak in December 2019 and some effective measures were required. Sharp accepted the request made by Columbia University and agreed to fund the study and provided necessary test equipment. Afterwards, the study was conducted independently by the University, leading to the results outlined above.

For more than 20 years since 2000, Sharp has promoted academic marketing*5 to demonstrate the effectiveness of Plasmacluster technology at independent third-party testing institutions in Japan and overseas. Thus far, including this demonstration, 13 testing institutions outside of Japan have proven its effectiveness in suppressing the action of harmful substances such as airborne Serratia bacteria which is a source of hospital-acquired infections (Dr. Melvin W. First, US), airborne influenza viruses (Institute Pasteur, Vietnam), and clinical effectiveness in reducing the risk of tuberculosis infections in tuberculosis hospitals (National Center of Tuberculosis and Lung Diseases, Georgia). Furthermore, the mechanism of action in suppressing viruses, fungi, and bacteria (Professor Gerhard Artmann, Germany) has been clarified. At the same time, Sharp has continued to verify the safety of Plasmacluster technology over the course of many years.

Sharp will continue to actively demonstrate the effectiveness of Plasmacluster technology not only in Japan but also internationally in order to make further social contribution.

■ Overview of Airborne Coronavirus Verification Test

• Study conducted by: Prof. Moriya Tsuji (Columbia University Department of Medicine)

　Note: Researchers who have contributed in this study: Dr. Yaoxing Huang, Dr. Manoj Nair,
　 Dr. Kazuya Masuda, Dr. Hiroshi Mohri, Yukiko Tsuji, Patrick Loughlin, Dr. David D Ho

• Test space: A test box having a volume of 102 liters inside a safety cabinet

• Verification test apparatus: Virus testing device equipped with Plasmacluster technology

• Plasmacluster ion density: Approx. 25,000 pcs/cm3 (in the center of test chamber)

• Control study: Comparison using the aforementioned device without ion generation (blowing air only)

• Verification virus: SARS-CoV-2 (Omicron BA.1 variant)

• Test method:

A solution containing SARS-CoV-2 that had been highly concentrated by centrifugation was sprayed into a 102-liters test chamber and exposed to Plasmacluster ions. Subsequently, the airborne virus inside the chamber was recovered. The virus infectious titer was measured using a TCID50 assay*6.

*6 A standard assay involving inoculation of cells with stepwise diluted virus solution and checking the infectivity titer.

Figure 1. Image of test equipment