Researchers just created an air filter that kills the coronavirus

Remember when we were all hoping the warm summer weather would swiftly push the coronavirus under the rug and out of our collective lives? It was a nice, comforting thought, but reality has refused to cooperate. As the days, weeks, and months have passed by it’s become woefully apparent that COVID-19 has no plans of going anywhere anytime soon.

A vaccine is still our best bet at moving past this pandemic, but that’s a long way away even according to the most optimistic of projections. In the meantime, though, an innovation from the University of Houston may just become an integral part of beating this virus. Researchers at UH have developed a “catch and kill” air filter that’s capable of instantly capturing and neutralizing the coronavirus.

In test simulations, the filter showed the ability to kill 99.8% of the novel SARS-CoV-2 in just a single pass through. Additionally, it killed 99.9% of exposed anthrax spores. The filter itself is made up of easy to find, commercially available nickel that’s then heated to roughly 392 degrees Fahrenheit.

“This filter could be useful in airports and in airplanes, in office buildings, schools and cruise ships to stop the spread of COVID-19,” says corresponding study author Zhifeng Ren, director of the Texas Center for Superconductivity at UH, in a university release. “Its ability to help control the spread of the virus could be very useful for society.” 

In addition to the team at UH, this research was also made possible by Medistar, a Houston-based medical real estate development firm. Medistar executives are already talking about developing a smaller, desk-top version of the air filter that could be placed on worker’s desks. 

It’s generally agreed upon that the coronavirus can stay active in the air for around three hours. So, the research team knew that developing a filter capable of quickly doing away with the virus could greatly mitigate its spread in closed, air-conditioned spaces. It’s also known that the coronavirus can’t survive past the heat threshold of 158 degrees Fahrenheit. With this in mind, it wasn’t a tough choice for the team to go with a heated filter. 

Nickel foam was chosen because it’s porous and flexible, facilitating the flow of air. It is also electrically conductive and thus easily heated. However, nickel foam also has low resistivity, meaning it’s somewhat difficult to quickly heat it to the temperatures needed to kill the coronavirus. Researchers fixed this problem by folding the foam and then connecting various areas with electrical wires. This increased the nickel foam’s overall resistance, allowing a faster and more efficient heating up process.

The fact that the filter is electronically heated, instead of via an external source, also helped mitigate the escape of heat from the filter. This is important because it means the filter won’t interfere with nearby AC units. According to Ren, the filter meets all requirements for heating and ventilation/AC systems. 

“This novel biodefense indoor air protection technology offers the first-in-line prevention against environmentally mediated transmission of airborne SARS-CoV-2 and will be on the forefront of technologies available to combat the current pandemic and any future airborne biothreats in indoor environments,” explains co-first study author Dr. Faisal Cheema of the UH College of Medicine.

The filter’s developers would like to see a slow yet steady rollout of the device “beginning with high-priority venues, where essential workers are at elevated risk of exposure (particularly schools, hospitals, and health care facilities, as well as public transit environs such as airplanes.)”

The phrase “necessity is the mother of invention” is as true today as it was thousands of years ago when Plato first spawned the saying in The Republic. This filter is a great example of human ingenuity and creativity in the face of a unique threat.

The full study can be found here, published in Materials Today Physics.