New method can neutralize coronaviruses with mineral nanoparticles

A new way to neutralize the coronavirus and other membrane-surrounded viruses has been discovered by researchers from the Swedish University of Agricultural Sciences and the University of Tartu. Certain mineral nanoparticles were found to damage the membrane of the virus, making it less able to enter human cells. The mode of action that is demonstrated has not been discussed in previous research. The technology works at room temperature and also in the dark, offering a range of benefits for disinfecting surfaces, air and water.

"Using this new knowledge, it should be easy to create surfaces with antiviral properties by simply spraying them with aqueous solutions of suitable nanoparticles and letting them dry. It should also be easy to design cost-effective filters to purify contaminated air and water," says Professor Vadim Kessler from SLU who has led the work.

The recent COVID-19 pandemic has led to an intense search for new types of treatments and disinfection methods that can be used in outbreaks of viral diseases of this type. One area that has received much attention is nanotechnology, as tiny particles of certain metals and metal oxides have been shown to have anti-viral properties.

Now, researchers from SLU and the University of Tartu in Estonia have studied the outcome when certain types of mineral nanoparticles come into contact with a coronavirus, and they discovered a mode of action that has not been proposed before.

We now understand what properties such particles need to have to be effective against the coronavirus, and this is a very important step forward."

Professor Vadim Kessler from SLU

Coronaviruses belong to a type of virus that has an outer envelope, a lipid membrane. It turned out that nanoparticles of sand minerals such as titanium oxide bind very strongly to phospholipids in this membrane. This damages the membrane and leads to the release of viral genetic material, thereby making the virus less able to infect cells.

A major advantage is that this happens at room temperature and that it does not require any kind of activation. Previously, it was believed that mineral nanoparticles could only destroy viruses by producing so-called reactive oxygen species, which would require illumination with UV light.

The study thus suggests that surfaces coated with titanium nanoparticles can destroy enveloped viruses such as coronaviruses and influenza viruses without needing to be activated by UV light, and thus can work in dark spaces. Other small metal oxides that bind strongly to phospholipids, such as iron and aluminum oxides, could work in the same way. Another possible application could be to purify contaminated water in emergencies by adding a nanopreparation and allowing the resulting gel to settle.

"The particles we produce are not dangerous to the human body," adds Angela Ivask, who is Professor of Genetics at the University of Tartu. "We have tested them on several cell lines to assure this."