Spray lights you up when you've got poison ivy
Scratch that itch. Chemists develop a spray-on substance that can identify the presence of urushiol, the oily sap on poison ivy that surely comes from the devil himself.
I have not yet had the good fortune of getting poison ivy, and now perhaps I never will. A new spray that lights up in the presence of the oil that causes the rash might let me bail on that particular party should I ever be invited.
Rebecca Braslau, a professor of chemistry at the University of California at Santa Cruz, has concocted a nontoxic spray that goes fluorescent in the presence of urushiol, the oily sap on poison ivy leaves that can make life extremely unpleasant for you and your skin.
Braslau and colleagues describe their innovation in a recent issue of The Journal of Organic Chemistry. Their paper, titled "Urushiol Detection Using a Profluorescent Nitroxide," might just as well be called "Spray This Stuff on to Maybe Avoid Scratching Yourself Silly."
The creation is of personal interest to Braslau, who, like many, has had horrible reactions to poison ivy. She knows how to avoid the plant, but urushiol sometimes unwittingly makes it into her home via her husband, a geologist who spends a fair amount of time cavorting with nature.
"When we first got together he wasn't very careful about it, and so he would get it on his arm and he wouldn't even know it," Braslau told NPR science correspondent Joe Palca. He'd put his arm around her and she'd start itching. So Braslau got to thinking: "There's got to be some way to deal with this, and I just had this eureka moment because I thought about it for a couple years."
The spray involves a class of chemical compounds called nitroxides. The UCSC research team developed a nitroxide-based solution that reacts to the oil on poison ivy leaves, then added a fluorescent dye that lights up to spotlight the reaction when it occurs.
The idea is that being alerted to exposure could prompt immediate measures such as using TecNu, an over-the-counter water-free skin cleanser that removes the plant oils from poison ivy, poison oak, and poison sumac.
Breslau has a patent, and she and her team are currently working to improve their product. Until thorough safety tests have been performed, she says it's probably best to use the spray on objects such as shoes or backpacks rather than skin. She is, however, itching for the day when she can spray it directly onto herself -- and her husband.