A bioactive coating would increase the effectiveness of masks – Le Courrier Sud

MONTREAL — A bioactive coating developed by a team from Quebec and Brazil would allow surgical masks to not only block viruses but also destroy them.

The researchers tested three different coatings, including one that destroyed almost all viruses deposited on the surface of the mask in less than a minute.

“We are depositing a very thin layer of a few dozen atomic layers,” Professor Diego Mantovani, head of the Laboratory of Biomaterials and Bioengineering at the University of Laval, told La Presse Canadienne. We change the way the material interacts with the environment.”

Right now, he said, surgical masks act as a barrier that traps most, but not all, bacteria and viruses.

Additionally, certain viruses, such as COVID-19, can survive on the surface of the mask for several hours. And coughing, talking, sneezing or a runny nose can reduce the filtering performance of masks, which is why it’s important to replace them after a few hours.

The research team from Quebec and Brazil therefore tested three molecules known for their bioactive properties in the laboratory. These molecules were attached to surgical mask fabric samples contaminated with a coronavirus using plasma technology.

The researchers tested a coating made from polyethyleneimine (PEI), a polymer found primarily in detergents; a coating of PEI and lauric acid, a fatty acid found in coconut; and a coating of PEI and copper sulfate.

The amount of virus deposited on the first two coatings was 99% melted after two hours. But by the third coating, 99.99% of the viruses were killed in less than a minute, possibly because the copper had penetrated the viral membrane and allowed the PEI to get inside.

The bioactive coating was applied to the external surface of the masks to trap viruses at the time of inspiration. In theory, it could also be placed on the inner surface of the mask to prevent the wearer from contaminating those around them. However, more testing is needed before this can happen, said Professor Mantovani.

“Because it’s natural materials, it probably wouldn’t have a very long lifespan, we wouldn’t be able to use the mask for several days,” he said. But for a couple of hours of interaction, I think it’s a product to consider.”

The researcher believes that such masks could be particularly useful in environments where the risk of infection is high, such as in a hospital emergency room, during a concert in a crowded amphitheater or on a plane trip.

In large-scale production, the researchers estimate that the additional coatings would only increase the cost per mask by around ten cents.

The results of this study were published in the journal Applied Surface Science.