Being a visual species, we usually believe what we see. That’s frequently the case with medicine, where a person’s visual appearance coupled with a peek at the insides courtesy of an X-ray or CAT scan might be enough to diagnose a disease. Cancers are often detected using imaging equipment, but some chemists think smelling a tumor might be better medicine than simply seeing it.
George Preti, a professor at the University of Pennsylvania, is one of them. He’s developed an electronic sniffer that detects various scents the human body gives off. Here’s Veronique Greenwood, writing for the New York Times Magazine:
Electronic noses have the potential to detect even very small amounts of molecules — but they need to be programmed to look for specific signs wafting up from patient samples. To do that, A.T. Charlie Johnson, a physicist and collaborator of Preti’s at Penn, has the electronic nose sniff blood samples from both sick and healthy patients. As the air passes through the tube, molecules from the samples alight on strands of sticky DNA attached to the carbon nanotubes, changing the electrical signals running out of the box. The team can look for patterns in the signals and use the difference — if there is one — between cancer samples and healthy samples to create an odor-based ovarian cancer test.
Smelling diseases isn’t necessarily new—there are plenty of ailments that doctors diagnose based on odor. There are even dogs that can pick up on the subtle changes in a person’s bouquet, alerting their master to the presence of cancer, impending diabetes-related hyper- or hypoglycemia, and even heart attacks. Preti and his colleagues hope that develop devices that mimic that keen sense of smell but are available to labs 24 hours a day.