A mask with a reusable respirator that captures and kills the novel coronavirus—that’s the vision of South Dakota State University assistant mechanical engineering professor Saikat Basu. He is part of a multi-institutional team of researchers who will be designing and developing the new respirator.

“This pandemic is not going away any time soon—the idea is to have better technologies to reduce virus transmission in hospital settings and to protect uninfected populations,” said Basu, who is the first SDSU faculty member to receive National Science Foundation funding for COVID-19 research.

To develop the new respirator, Basu will be collaborating with associate professor Sunghwan “Sunny” Jung of Cornell University and associate professor Leonardo Chamorro of the University of Illinois Urbana-Champaign. The project, which is expected to begin in May, will be supported by a 1-year, $200,000 grant obtained through the NSF Rapid Response Research funding mechanism.

This respirator filters the air a wearer breathes. By comparison, N95 respirators use what are known as passive filters to prevent the wearers from inhaling airborne particles. “They do nothing to kill the virus,” Basu pointed out. As the wearer breathes, Basu’s model will actively capture virus-carrying aerosol droplets and then inactivate them.

The respirator’s internal structure will be modeled after the nasal passages of animals, such as pigs and dogs, which have a very sensitive sense of smell. This unique design will help isolate the droplets and embed them in the respirator, explained Basu, who will do 3D modeling of the aerosol droplets to figure out the best possible respirator design. One doctoral student will also work on the project.

During the last 4 years, Basu had been modeling aerosol sprays designed to help patients with chronic sinus problems for a research group at the University of North Carolina Chapel Hill Medical School. He began working on the National Institutes of Health project as a postdoctoral researcher in April 2016 and has continued working with the UNC group since coming to SDSU in January 2019. Through this period, Basu has also published almost a dozen journal papers on intranasal transport and topical drugs.

For the COVID-preventive respirator in addition to its unique structure, the new design will use a combination of copper-based filters and temperature changes to help the droplets adhere to the respirator walls and to kill the virus. “Both the geometry and a cold temperature on the surface walls will help the droplets condense,” he said. Then a combination of raising the temperature of the walls and the effect of ions generated from copper wires in the filter will help inactivate the virus. Recently published studies have supported the use of these two mechanisms on earlier and current strains of coronavirus.   

“It takes about 50 minutes to inactivate the virus,” Basu said. “We envision the respirator will be a removable piece that can be washed each day and then reused.” Once the prototype has been completed, the researchers will collaborate with a biosafety level 3 laboratory to test their design using live virus.