A filter composed of polymer nanothreads completely changed the view for three commercial masks by arresting 99.9% of coronavirus aerosols in an experiment.
“The work is the first study to that uses coronavirus aerosols to examine filtration efficiency of air filters and face masks,” said the co-author of a study behind this finding. Previous studies have used surrogates of polystyrene beads, saline solution, and bacteriophages.
The study proves the effectiveness of surgical and cotton masks, electrospun nanofiber membranes, and a neck gaiter to remove coronavirus aerosols for prevention of airborne transmission. In fact, the neck gaiter and cotton masks removed only approximately 45- 73% of aerosols. On the other hand, surgical mask performs much better eliminating 98% coronavirus aerosols. And, nanofiber filter almost completely removed all of the coronavirus aerosols.
Meanwhile, the study of contagious new virus is dangerous and is performed in labs with the highest biosecurity rankings, which are relatively rare. In fact, all studies till date on mask or filter efficiency during the pandemic have used other materials have used other materials to imitate the size and behavior of coronavirus aerosols. Improvising on this, the new study tested both aerosolized saline solution and an aerosol containing coronavirus that belongs to the same family of viruses that causes COVID-19, but only causes infection in mice.
The study effort led to the production of nanofiber filter by transmitting a high electrical voltage through a speck of liquid polyvinylidene fluoride. This is to spin threads with the diameter of about 300 nanometers, which makes it about167 times thinner than a strand of human hair.