Take the Sting Out of Mosquitos

Engineering researchers find a promising new tool to stop bites: graphene

SOMETIMES, SCIENTIFIC breakthroughs are made when researchers are looking for something else.

Robert Hurt, professor in Brown’s School of Engineering and leader of the university’s Superfund Research Program, had been working with his team on fabrics that incorporate graphene as a barrier against toxic chemicals. “We started thinking about what else the approach might be good for,” he recalled.

A novel idea emerged from the brainstorming: mosquito bite protection.

In a paper published in Proceedings of the National Academy of Sciences, Hurt’s lab showed that multilayer graphene can provide a two-fold defense against mosquito bites. The ultra-thin material acts as a barrier that mosquitoes are unable to bite through. Experiments also showed that graphene blocks chemical signals mosquitoes use to sense that a blood meal is near, blunting their urge to bite.

The study was based on research with participants who placed their arms in a mosquito-filled enclosure so that only a small patch of their skin was available to the mosquitoes. Researchers compared the number of bites participants received on their bare skin, on skin covered in cheesecloth, and on skin covered by a graphene oxide film sheathed in cheesecloth. Cintia Castillho PhD ’20, the study’s lead author, said the graphene material “was a chemical barrier that prevents mosquitoes from sensing that someone is there.”

Within days of its release, the study—funded by the National Institute of Environmental Health Sciences, the Superfund Research Program, and the National Science Foundation—drew a large amount of international media and scientific attention. Hurt said properly engineered graphene linings could be used to make mosquito-protective clothing, and “there’s a lot of interest in non-chemical mosquito bite protection.”—Kevin Stacey