“Our biomedical engineering lab has developed a way to potentially neutralize viruses lingering in the air using aerosols of FDA-approved food coloring dyes,” the team announced.
Aerosols, tiny droplets that linger in the air, are the main way that COVID-19 is suspected to travel through the air and infect others. Because of this, it is important to find a way to sanitize the air indoors, so people can gather with less risk of transmission.
“We do have several different techniques or approaches for surface disinfection, but we don’t have any good method to clean or disinfect air when we have any indoor settings and activities and etc,” Associate professor and researcher Young Kim said.
The process the research team came up with was inspired by a medical treatment known as photodynamic therapy, often used to treat certain types of cancer.
“Photodynamic therapy (PDT) is a two-stage treatment that combines light energy with a drug (photosensitizer) designed to destroy cancerous and precancerous cells after light activation,” the Mayo Clinic reported.
The photosensitizer reacts with oxygen in the presence of light, producing oxygen-free radicals. These radicals can kill off harmful pathogens.
“There are lots of good medical PDT chemicals that are also known as photosensitizers but instead of using expensive medical photosensitizers, we identified a few FDA-approved food coloring dyes that can generate very similar effects (in visible light),” Kim said.
The researchers explained that by generating small aerosols containing food coloring, the dyes can float and linger in the air — without staining surfaces.
“We used this technique to produce a device, Photodynamic Airborne Cleaner, that disinfects pathogens floating in the air,” the researchers said.
They added that photodynamic therapy was first demonstrated as a means of fighting bacterial infection. So, this new discovery that it may be useful for inactivating viruses could be a breakthrough when it comes to controlling the spread of COVID-19.
The report notes that there are other disinfection techniques available, such as hydrogen peroxide or “deep UV” illumination — however, these are often more useful when it comes to disinfecting surfaces, rather than the air.