The researchers suggest that the new spray can reportedly protect against both viral and bacterial pathogens that affect the respiratory system, explaining that the majority of respiratory viruses — like the flu and COVID-19 — tend to enter the body via the nose. Droplets containing the virus are typically released when an infected person exhales, sneezes, coughs or laughs, which others then inhale. These pathogens then attach to the nasal lining, where they replicate and are further spread.

The new spray, dubbed Pathogen Capture and Neutralizing Spray (PCANS), was developed using ingredients from the U.S. Food and Drug Administration's (FDA’s) Inactive Ingredient Database (IID) and Generally Recognized as Safe (GRAS) list.

“We developed a drug-free formulation using these compounds to block germs in three ways — PCANS forms a gel-like matrix that traps respiratory droplets, immobilizes the germs, and effectively neutralizes them, preventing infection,” the researchers explained.

When tested in the lab using a 3D-printed model of the human nasal cavity, the PCANS trapped twice as many droplets when compared to natural mucus alone. This is because the PCANS formed a gel that behaves as a solid barrier that blocks and neutralizes nearly 100% of all viruses and bacteria the team tested — including Influenza, SARS-CoV-2, RSV, adenovirus and K Pneumonia, among others.

The researchers also discovered that when tested on mice, a single dose of PCANS nasal spray blocked infection from the lethal PR8 strain of influenza at 25 times the lethal dose. Further, in mice treated with the nasal spray, virus levels in the lungs dropped by over 99.99%.

An article detailing the nasal spray, “Toward a Radically Simple Multi-Modal Nasal Spray for Preventing Respiratory Infections,” appears in the journal Advanced Materials.