University Develops Virus-Killing Coating
Researchers from The University of Queensland have recently developed an effective, antiviral surface coating technology against SARS-CoV-2, the virus that causes COVID-19.
Designed to use as an extra layer of protection against COVID-19 and the flu, the spray-applied technology for surfaces and face masks was developed with Boeing as a joint research project and was tested at the Peter Doherty Institute for Infection and Immunity at The University of Melbourne.
According to UQ’s Australian Institute for Bioengineering and Nanotechnology researcher Professor Michael Monteiro, the water-based coating technology works by deploying worm-like structures that attack the virus.
“When surgical masks were sprayed with these ‘nanoworms,’ it resulted in complete inactivation of the Alpha variant of SARS-CoV-2 and influenza A,” Monteiro said. “These polymer ‘nanoworms’ rupture the membrane of virus droplets transmitted through coughing, sneezing or saliva and damage their RNA.
“The chemistry involved is versatile, so the coating can be readily redesigned to target emerging viruses and aid in controlling future pandemics,” Monteiro added.
Monteiro went on to explain that while face masks should still be used in preventing or reducing community spread of COVID-19, the applied coatings could further reduce the chance of infection and would help to provide long-lasting control measures to eliminate both surface and aerosolized transmission.
“We know that COVID-19 remains infectious for many hours or days on some surfaces and provides a direct route to infection,” said Monteiro. “Therefore, there is greater emphasis on eliminating both surface and airborne transmission to complement vaccination of the population to stop the current pandemic.”
The university reports that in addition to its water-based properties, the coating is environmentally friendly, and its synthesis aligns with manufacturing techniques used in the paint and coatings industry.
Research on the newly developed coating has since been published in ACS Nano.
Coatings Fighting COVID-19
Not long after the initial coronavirus outbreak, researchers from all over the world started looking into coatings solutions to help combat the virus’ spread.
In May of last year, researchers at the Hong Kong University of Science and Technology announced that they’d developed a multilevel antimicrobial polymer (MAP-1) coating effective in killing viruses, bacteria and spores.
While the coating was confirmed to be effective against drug-resistant microorganisms in the healthcare space (including two field studies in the Kowloon Hospital and Haven of Hope Woo Ping Care and Attention Home), the team also worked with the Water Supplies Department and the Drainage Service Department to field-test the coating in infrastructure projects as well.
The coating was developed by a team led by professor Yeung King-lun, of the Department of Chemical and Biological Engineering and the Division of Environment and Sustainability.
According to the university: “MAP-1 coating provides lasting protection and surface disinfection against microbial contamination. This product is designed for use on different surfaces including metals, concrete, wood, glass, plastics as well as fabrics, leathers and textiles without changing the materials’ appearance and tactile feel.
"According to the Technical Standard for Disinfection issued by the National Health Commission in Mainland China, the coating is proven to be non-toxic and is safe for skin and the environment, hence it also allows MAP-1 to be made into hand sanitizers, paints and coating, filter materials for air and water purification, as well as clothing and surgical masks to safeguard the health of the individual and public.”
The coating reportedly prevents microbial adhesion on a surface by using the special blend of antimicrobial polymers, effectively killing “99.9% of bacteria and viruses.”
The following month, teams at Montreal’s Concordia University were looking into antiviral metallic and ceramic coatings as a way to slow the transmission of COVID-19. The Surface Engineering for Advanced Manufacturing (Green-SEAM) Network, which is based at Concordia, was putting its researchers to work to see how its resources can be applied to the pandemic.
“Copper and titanium oxide, we know, are active in killing bacteria and viruses, so they are effective materials to spray on surfaces to fight the spread of COVID-19,” said Christian Moreau, Director of Green-SEAM and Canada Research Chair in Surface Engineering, at the time.
“We have a unique network of experts in surface engineering from 11 universities across Canada, 14 industrial companies and government laboratories including the National Research Council who specialize in coating materials.”
Recent work at the University of Toronto by professor and Green-SEAM member Javad Mosthaghimi has demonstrated the benefit of the copper coatings on hospital waiting-room chair armrests, according to the university.
And, for the past five years, experts at Concordia’s Gina Cody School have been tailoring the structure of titanium oxide coatings to optimize their photocatalytic and filtration properties that can now be deployed for their antibacterial and antiviral capabilities.
In July, new research was announced to be underway at the Waterloo Institute for Nanotechnology within the University of Waterloo to develop a coating that officials say aimed to “kill the COVID-19 virus immediately upon contact with any surface.”
Researchers, who were collaborating with SiO2 Innovation Labs, were looking for the antiviral coating to be applied to surfaces such as personal protective equipment and high-touch surfaces. The coating creation has been a multi-step process, the university says, that combined a computational model and studies on different coating materials.
The team has reportedly developed an experimental set-up to quantify the adhesion force between the virus and the coated surface. Lead researcher Sushanta Mitra used water droplets to mimic the primary mode of transmission of COVID-19 between humans.
That same month, researchers at the Okanagan Polymer Engineering Research and Applications Lab (OPERA), at the University of British Columbia Okanagan, reportedly developed a coating that researchers said repels nearly all substances off a surface.
The spray-on solution aims to make any surface omniphobic, according to master’s student Behrooz Khatir, the author of a recent study on the project.
The two-layer coating involves placing an ultra-smooth silica layer on a surface and then functionalizing this layer with a highly reactive silicone to block all kinds of liquids from sticking on the surface, said Kevin Golovin, assistant professor at OPERA. The researchers note that in addition to its versatility, the coating is also durable, able to withstand exposures to UV light, acids and high temperatures.
Golovin recently received COVID-19 funding from the Natural Sciences and Engineering Research Council to optimize the coating for healthcare face shields.
The research was recently published in the journal, ACS Applied Materials & Interfaces.