Mosquito-Repellent Coating Combats Disease
Decorative paints company Coral, an AkzoNobel-owned brand, has recently developed a mosquito-repellent coating to fight against dengue fever in Brazil.
“Public health is a major issue in countries across the world. In Brazil, dengue is a particular problem,” said Daniel Campos, AkzoNobel’s Director of Decorative Paints in Latin America. “We want to help people look after their families by offering a breakthrough product which has been proven to give continuous protection against the Aedes aegypti mosquito, 24 hours a day, for up to two years.”
Repellent Coating Technology
Over the first few months of 2022, it was reported by the Brazilian Ministry of Health that dengue surged by 165% in the country. Largely responsible for the spread of the viral illness are infected Aedes aegypti mosquitos, which can transfer dengue to humans through their bite.
Up until May 14 this year, there were 855,910 reports of probable infection of dengue in Brazil, with an incidence of 401.2 per 100,000 inhabitants.
According to the World Health Organization, the global incidence of dengue has grown dramatically, with around half the world’s population at risk. In addition to dengue, Aedes aegypti are also capable of spreading zika and chikungunya viruses.
AkzoNobel reports that the extent of the public health problem is underlined by the fact that dengue, zika and chikungunya don’t have specific treatments, meaning that prevention is currently considered to be the best strategy.
“Concerns about health and safety at home have greatly increased in recent years,” explained Campos. “This new coating – the first of its kind in the region – is a clear matt varnish which can be applied over any painted wall.
“It’s a great example of People. Planet. Paint. in action and shows how our pioneering approach to product development can help make a genuine and lasting difference, including to people’s health and well-being.”
Specifically designed to combat the Aedes aegypti mosquito, the Well-being Protection Anti-Mosquito transparent coating was tested in an independent external laboratory, certified by the Brazilian Network of Analytical Laboratories in Health.
The transparent coating utilizes permethrin—notably known for its repellent properties and use in fabrics for mosquito nets and protective clothing—as an active ingredient within its varnish matrix.
Taking place on painted walls and ceilings in a life-size house environment, researchers conducting the study found that when a mosquito landed on the transparent topcoat, the permethrin was absorbed through its feet and over-excited the insect’s nervous system, causing it to disengage or fall off.
Currently only available in Brazil, there are plans to make Well-being Protection Anti-Mosquito available in other countries and regions.
Other Protective Coatings
Last month, the European Space Agency recently announced that it is studying materials for self-cleaning antimicrobial coatings to protect both astronauts and materials on the International Space Station.
The PATINA project, or “Optimization of Photo-catalytic Antibacterial coatings,” was proposed through the ESA’s Open Space Innovation Platform, which seeks novel ideas for space research. According to the release, the project also covers other antimicrobial surface treatments, including super-hydrophobic materials that repel all moisture, electro-static reaction and biocide-releasing materials.
A microbial survey of surfaces on the ISS reportedly found dozens of different bacteria and fungi species, including pathogens such as Staphylococcus aureus which can cause skin and respiratory infections as well as food poisoning. Biofilms from theses microbial populations can also tarnish and eat away at metla, glass, plastic and rubber on the spacecraft.
To combat this, the IIT team started working with titanium oxide, or titania, which is used in self-cleaning glass or hygienic surfaces on Earth. When exposed to ultraviolet light, the material breaks down water vapor in the air into “free oxygen radicals” that eat bacterial membranes.
According to the ESA, the coating was successfully tested on glass, silicon wafer, aluminum foil and clean-room grade paper tissue. This testing was completed through a variety of methods, including physical vapor deposition and atomic layer deposition.
In January, researchers from the University of Waterloo discovered that by applying a thin-film coating of copper or copper compounds on surfaces, SARS-CoV-2—the virus that causes COVID-19—could be more easily inactivated or destroyed.
The engineering graduate students from the university were reported to have first launched the study shortly after the pandemic hit in March 2020.
For their research, the team of students investigated how six different thin metal and oxide coatings interacted with HCov-229E, a coronavirus that is genetically similar to SARS-CoV-2, but safer to work with.
To test the different coatings, the Waterloo students partnered with Wilfrid Laurier University researchers to apply the materials on glass and N95 mask fabric at a thickness roughly 1,000 times thinner than a human hair. Once coated, the fabric and glass pieces were either submerged in a viral solution or exposed to small droplets.
After the virus was removed from the coatings, each extract was placed in contact with healthy cells and measured for its ability to replicate. According to the researchers’ findings, only the copper and the copper-containing compounds had antiviral effects.
The researchers’ antiviral coating could be applied to high-touch public surfaces and has the ability to be tailored in a way that enhances its interaction with the viral droplet and the antiviral effects.
During the next steps, the Waterloo research group planned to develop coating techniques for masks and is continuing to explore the dissolution process for smaller droplet sizes, as well as investigating how to control the adhesion of copper films to various surfaces.
In August 2021, researchers from Chalmers University of Technology (Gothenburg, Sweden) reported that they developed a new method to prevent infections—by utilizing graphene coatings. More specifically, by covering graphene-based material with bactericidal molecules.
According to the university, certain bacteria can form impenetrable surface layers, or “biofilms,” on surgical implants and represent a significant problem for the healthcare community. Biofilms are also reportedly more resistant than other bacteria, and the infections are therefore often difficult to treat. In addition to the effects on patients, this is also costly to healthcare providers.
In the study, the graphene material was covered with usnic acid, which is extracted from lichens. Usnic acid was chosen because previous research has shown that usnic acid has good bactericidal properties. According to Chambers, it works by preventing bacteria from forming nucleic acids, especially inhibiting of RNA synthesis, and thus blocking protein production in the cell. Usnic acid was specifically tested for its resistance to the pathogenic bacteria Staphylococcus aureus and Staphylococcus epidermidis, two common culprits for biofilm formation on medical implants.
The researchers’ new material reportedly displayed a number of promising properties. In addition to successful results for integrating the usnic acid into the surface of the graphene material, they also observed that the usnic acid molecules were released in a controlled and continuous manner, thus preventing the formation of biofilms on the surface.
And, in December 2020, Teck Resources Limited (Vancouver, Canada) announced that it would be testing its antimicrobial copper coatings on high-touch transit surfaces.
The project was dubbed as the first of its kind on a transit system in North America and was being conducted in partnership with TransLink, Vancouver Coastal Health, VGH & UBC Hospital Foundation, Coalition for Healthcare Acquired Infection Reduction, and the University of British Columbia.
Through the company’s Copper & Health Program, Teck believed that as a major copper producer it could help to increase the use of antimicrobial copper in both healthcare facilities and public spaces to reduce the spread of infections, in addition to raising awareness and improving health outcomes for those most at risk.
According to Teck, copper alloy surfaces are naturally antimicrobial with self-sanitizing properties, with research showing that these surfaces eliminate up to 99.9% of harmful bacteria and viruses. Its latest pilot project, fully funded by the company itself, hosted four-week-long initial phases where various copper surfaces were installed on two buses on high-ridership routes and two SkyTrain cars in Vancouver.