Copper-based technology reduced viral activity by 99,99%. Virucidal microparticles can also be used in plastic and metal parts
An antiviral and antibacterial additive based on copper microparticles (copper powder), developed by Unicamp, inactivated the coronavirus, which causes Covid-99,99, by 19%. The result was observed after two hours of exposure of the microorganism through contact with the surface covered with the additive paint. The virucidal additive can be mixed with common wall paints and also incorporated into the manufacture of metallic and plastic objects, such as door handles, support bars for public transport vehicles and elevator buttons.
The composition, developed by researchers from the Faculty of Mechanical Engineering (FEM) and the Faculty of Applied Sciences (FCA), was characterized in tests conducted at the Institute of Biology (IB) at Unicamp. The invention had a patent application filed by the Inova Unicamp Innovation Agency and can now be licensed for use in industry while the National Institute of Industrial Property (INPI) analyzes the documentation.
“We use microparticles measuring 20 to 60 micrometers. The size facilitates incorporation into final products, as there is no need for other industrial equipment. They do not affect physical properties, such as color and texture, and, in addition, the technology is safer compared to the use of copper nanoparticles, which are more difficult to disperse and incorporate”, says professor and researcher at Unicamp Laís Gabriel.
Smaller than a grain of sand
The copper powder production process has simple routes, which do not alter processes already conducted by the industry, explains professor and researcher Éder Lopes. Metallic powder has particles ten times smaller than those of a grain of sand. In addition to the shape, the nature and size of the copper are controlled to achieve the antiviral effect.
“We realized that copper oxide is better than copper in pure form as it has a less homogeneous particle shape, which favors the deactivation of viruses. The production route and application also have easy commercial capillarity, as they do not require prior preparation or changes in the paint dilution process that painters already carry out”, he explains.
Copper microparticles can be obtained by traditional grinding, with gas and water jets (atomization), or by electrochemical process (electrodeposition). In tests, ground copper was added to water-based white paint, without the need for mixers or special equipment, and did not alter the original appearance of the product. The technology also allows the use of recycled copper, reducing production costs.
Another advantage is that the additive has a low concentration of copper oxide, between 5% and 15%, which makes the technology more competitive. “In all concentrations tested, we obtained equal results in inactivating the coronavirus, which leads us to think that a decrease in this percentage, important for the final cost of a product, would also not alter the effect”, comments Lopes.
How does anti-covid paint work?
Copper oxide particles work as a natural disinfectant. Paints and surfaces enriched with the additive trigger a process that destroys the virus's protective layer. Thus, when a person sneezes or coughs near a wall or handrail, for example, and the coronavirus deposits on this additive surface, it interacts with the copper particles and is destroyed.
The technological solution was designed for hospitals and places with large circulation of people, such as passenger terminals, schools and common areas in condominiums. Another possibility is incorporation into packaging, to reduce the risk of contagion on contaminated surfaces, explains the professor at the Institute of Biology, Clarice Arns, who coordinated the virus and toxicity tests.
“Copper is a very stable metal, cheaper than silver and recognized for its antiviral and bactericidal activity. In testing invitro, The copper oxide tested was not toxic to cell lines, which are extremely sensitive. The additive thus has broad application potential, such as in plastic food packaging”, points out the virologist.
The studies conducted by Arns were limited to evaluating the effect of copper for a maximum of 24 hours, which does not mean that the effect ends after this period. On the contrary, preliminary results indicate permanence and constancy. “The more time passed, the greater the virucidal power of the additive. After two hours of contact there was stabilization and the inactivation effect remained the same throughout the 24 hours”, comments the researcher.
The additive can be an ally in combating viral and bacterial infections caused by contact with contaminated surfaces, but it does not eliminate other sanitary measures, such as the use of masks and hand washing, as it is not effective in controlling the airborne transmission of diseases. and by contact between people.
Original article published on the Inova Unicamp Innovation Agency website.
