Stardust Powder Coatings, a manufacturer of powder coatings based in L'Aquila (Italy), has tested for the first time and with positive results an antiviral coating that can inhibit the human Coronavirus NL63.
In March, Stardust Powder Coatings has started the development and testing of coatings with antiviral properties.
Powder coatings with antiviral properties are special virucidal coatings that can inhibit the viruses present on the metal surfaces they are applied on. These coatings find wide application wherever it is necessary to reduce the risk of the active virus coming into contact with humans due to a contaminated surface.
While tests on other grades of powder coatings manufactured by Stardust Powder Coatings are currently underway, the company announced the first positive outcome for the Metalgrey 1050k product, a metallic epoxy powder coating that is widely used in the architecture and design sector.
The testing process
The tests, conducted by the Virology Research Services laboratory in London, were performed against the human Coronavirus NL63 according to the standard protocol ISO21702, which quantifies the antiviral properties of surfaces.
The protocol entails the dispensation of a pre-determined concentration of virus on a surface treated with the antiviral coating and on an untreated control surface. Both were incubated at room temperature for 24 hours in a humidified chamber.
Next, the samples were recovered by washing with media (neutraliser), and the amount of infectious virus in each suspension was quantified using a TCID50 assay. For the assay to be valid, the material tested must have no cytotoxic activity on the cells used to quantify the virus, nor interfere with cell sensitivity to infection.
In the material treated with Stardust antiviral coating, virucidal activity against human Coronavirus NL63 was observed with R value (antiviral activity) 1.34 at a contact time of 2 hours, and with R value 1.10 at a contact time of 24 hours. An R value greater than 1 is considered virucidal. Furthermore, no cytotoxic activity was detected against the cells used to quantify the virus.
"Surface hygiene is one of the fundamental factors to reduce cross-contamination - an extremely current need, especially in crowded places such as public buildings, schools, hospitals, transportation, gyms, restaurants or coffee shops", explains Guido Pozzoli, CEO of Stardust Powder Coatings. "To meet the growing demand for coatings that can ensure greater surface hygiene, we immediately set to work to bring the protective effectiveness of our coatings to the next level in order to provide an antiviral property as well", continues Pozzoli. "The future goal of Stardust is in fact to expand the range antiviral coatings to include any colour and finish, and any field of application".