This is Scientific American's 60-second Science, I'm Wayt Gibbs.
Imagine getting screened for early-stage lung cancer simply by taking a deep breath from an inhaler and then peeing into a cup. Sangeeta Bhatia, a professor of health sciences and engineering at M.I.T., described how that might be possible in a TED talk she gave in 2016: "What if you had a detector that was so small that it could circulate in your body, find the tumor all by itself and send a signal to the outside world? It sounds a little like science fiction. But actually, nanotechnology allows us to do just that." before they grow big enough to spread throughout the body and damage vital organs. "I dream that one day, instead of going into an expensive screening facility to get a colonoscopy or a mammogram or a pap smear,