Thin, flexible, lightweight graphene has become the popular chemical on the block. You can find the substance in helmets, tennis rackets, batteries, computers, and even shoes. A new study from Brown University reveals that graphene—derived from the same stuff as pencil lead—may help outwit mosquitoes too.
When a mosquito punctures the skin to feed on human blood, an itchy bump often appears. The bump usually clears up quickly. But sometimes mosquitoes carry serious diseases. The insects can also extract infected fluids and inject them into other victims. (Eeeew.) Mosquitoes could infect about a million people each year with diseases such as yellow fever, dengue, and malaria.
God created graphene, mosquitoes, and all things for His own glory. (Romans 11:36) He is not surprised at the intricate parts of a mosquito’s mouth or the potent, still-being-discovered uses for graphene. (For more about this ultra-thin, ultra-strong material, see Chemical Superhero: Graphene)
Like many important scientific findings, the graphene-vs.-mosquito breakthrough came during other research. A team from Brown was examining how graphene-lined clothing might protect the wearers against various poisons. The researchers “started thinking about what else the approach might be good for,” says Brown professor and study senior author Robert Hurt. “We thought maybe graphene could provide mosquito bite protection as well.”
The Brown team placed multiple layers of dry graphene film (known as GO) on the skin of study participants. The plucky subjects then jammed their arms into mosquito-filled boxes. Bingo! Skin covered by GO didn’t get a single bite.
“With the graphene, the mosquitoes weren’t even landing on the skin patch—they just didn’t seem to care,” says Cintia Castillho, the study’s lead author.
As it turns out, graphene packs a one-two punch against the bloodsuckers. First, as expected, pesky mosquitoes can’t poke through the tough material. Second, and perhaps most importantly, GO masks human skin and sweat chemicals that attract mosquitoes. Because graphene blocks out the chemical signals, mosquitoes simply don’t realize that a blood meal is just below the film.
To test GO’s strength against the mosquito’s proboscis (the long tube a female mosquito sucks blood with), researchers wet the GO with water or sweat. They found that mosquitoes can’t pierce dry GO, but they can jab right through wet GO. And in the case of human sweat on top of graphene, skeeters swarmed and stabbed like usual.
Researchers at Brown will continue to search for further uses for graphene. They’ll study how to fight disease-carrying mosquitoes without chemicals. And thanks to recent findings, graphene-infused clothing could help stop summertime scratching.
