Bacteria-Killing Material Developed for Surfaces
Researchers from the University of British Columbia (UBC) have recently developed a copper-coated technology capable of killing bacteria.
In an article, the university’s official independent newspaper The Ubyssey wrote that the material could be perfect for use in hospitals, campuses, or on high-contact surfaces like cell phone cases.
Starting back in the spring, mining company Teck Materials agreed to partner with UBC materials engineering professor Dr. Amanda Clifford. Together, the team installed adhesive copper patches in nine UBC Applied Science buildings. According to the university, the patches were designed to take advantage of the metal’s inherent anti-microbial properties.
As a result, the patch materials were reported to kill over 99% of bacteria within hours after contacting the surface.
While these tests were taking place within the science buildings, Clifford was working on how the bacteria-killing reaction times could be cut in half. In working to achieve this goal, Clifford and her team engineered a copper coating reinforced with nano-bumps.
The bumps, according to the research findings, worked to rupture bacteria cell walls. As an additional measure, the researchers also combined copper with zinc, another antibacterial element. The research from this experiment was later published in Advanced Materials Interfaces.
The team was also noted to apply for a provisional patent for the coating in July.
Since then, researchers have formulated a copper-based material with ease of use in mind. In starting with a copper patch on her phone, Clifford’s team is now looking at how the material can be tested for its anti-viral potential, which could expand the material’s usefulness.
“Copper has been registered as antiviral metal, but we want to see how our material works,” said Clifford.
To explore other high-traffic surface areas, the team is planning to place the engineered coating material in hospital settings to combat virus spreading. Gram-positive bacteria, like the colon-infecting Clostridioides difficile, are “a major source of infection within hospitals,” Clifford said.
The team hopes that with the new technology, the copper-based attachments can help prevent patients in hospitals from contracting viruses, or other infections like C. difficile, which have a fatality rate range of 6%-30%. The material would also help target the evolution of bacteria and fungi.
“We’re going to be in a very bad position globally if pathogens… or bacteria continue to become resistant to antibiotics,” she said.
By applying the bacteria-killing copper coatings and materials to hospital and high-traffic settings, Clifford explained that microbial populations could be prevented from evolving at all.
Other Copper Coating Research
In December 2020, diversified natural resources company, Teck Resources Limited (Vancouver, Canada) announced that it would be testing its antimicrobial copper coatings on high-touch transit surfaces.
The project was dubbed as the first of its kind on a transit system in North America and was being conducted in partnership with TransLink, Vancouver Coastal Health, VGH & UBC Hospital Foundation, Coalition for Healthcare Acquired Infection Reduction, and the University of British Columbia.
Through the company’s Copper & Health Program, Teck believes that as a major copper producer it can help to increase the use of antimicrobial copper in both healthcare facilities and public spaces to reduce the spread of infections, in addition to raising awareness and improving health outcomes for those most at risk.
The Copper & Health program focuses on three areas:
According to Teck, copper alloy surfaces are naturally antimicrobial with self-sanitizing properties, with research showing that these surfaces eliminate up to 99.9% of harmful bacteria and viruses. In its latest pilot project, fully funded by the company itself, will host a four-week-long initial phases where various copper surfaces will be installed on two buses on high-ridership routes and two SkyTrain cars in Vancouver.
An organosilane surface preservative will also be tested that has the potential to control and/or prevent the growth of microorganisms on treated surfaces.
The following year, in February, the U.S. Environmental Protection Agency registered copper surfaces for residual use against SARS-CoV-2, the virus that causes COVID-19.
As a result of EPA’s approval, products containing copper alloys can now be sold and distributed with claims that they kill certain viruses that come into contact with them. According to the EPA, this is the first product with residual claims against viruses to be registered for use nationwide. Testing to demonstrate this effectiveness was conducted on harder-to-kill viruses.
In the action, the EPA granted an amended registration to the Copper Development Association for “an emerging viral pathogen claim to be added to the label of Antimicrobial Copper Alloys- Group 1 (EPA Reg. No. 82012-1), which is made of at least 95.6% copper.”
Amended registrations allow previously registered products to make label changes (such as product claims or directions) and/or formulation changes. In this case, the amended registration is adding virus claims to the product registration.
The efficacy testing was supported by the Copper Development Association and conducted according to EPA's protocols. It reportedly demonstrated that certain high-percentage copper alloy products can continuously kill viruses that come into contact with them. Based on testing against harder-to-kill viruses, EPA expects these products to eliminate 99.9% of SARS-CoV-2, the virus that causes COVID-19, within two hours.
And in January of this year, researchers from the University of Waterloo discovered that by applying a thin-film coating of copper or copper compounds on surfaces, SARS-CoV-2—the virus that causes COVID-19—could be more easily inactivated or destroyed.
The engineering graduate students from the university were reported to have first launched the study shortly after the pandemic hit in March 2020.
For their research, the team of students investigated how six different thin metal and oxide coatings interacted with HCov-229E, a coronavirus that is genetically similar to SARS-CoV-2, but safer to work with.
To test the different coatings, the Waterloo students partnered with Wilfrid Laurier University researchers to apply the materials on glass and N95 mask fabric at a thickness roughly 1,000 times thinner than a human hair. Once coated, the fabric and glass pieces were either submerged in a viral solution or exposed to small droplets.
After the virus was removed from the coatings, each extract was placed in contact with healthy cells and measured for its ability to replicate. According to the researchers’ findings, only the copper and the copper-containing compounds had antiviral effects.
Additionally, lead study author Louis Delumeau, who recently graduated from Waterloo with a master’s degree in nanotechnology engineering, discovered that in some cases “nanoscale thin films of copper can come off from the surface and rapidly dissolve in virus-containing droplets, enhancing the virucidal effect.”
Due to this discovery, Delumeau believes that by adding an antiviral coating containing copper to the outside of a mask’s protective material or an inside filter could add an additional layer of safety.
The researchers’ antiviral coating could also be applied to high-touch public surfaces and has the ability to be tailored in a way that enhances its interaction with the viral droplet and the antiviral effects.
Moving forward, the Waterloo research group is developing coating techniques for masks and is continuing to explore the dissolution process for smaller droplet sizes, as well as investigating how to control the adhesion of copper films to various surfaces.
The study, Effectiveness of antiviral metal and metal oxide thin-film coatings against human coronavirus 229E, is authored by Louis Delumeau, Hatameh Asgarimoghaddam, Tamiru Alkie, Alexander James Bryan Jones, Samantha Lum, Kissan Mistry, Marc G. Aucoin, Stephanie DeWitte-Orr and Kevin P. Musselman and was recently published in the journal APL Materials.