A dog is “man’s best friend” in more ways than simply being a faithful and pleasant household companion. Specially trained service dogs have been used in medical clinics for therapy and comfort for the sick. More recently, an everyday dog’s acute sense of smell can act as a prototype for a new emerging tool that can save lives. Dogs are able to not only sniff out bombs, preform disaster relief and track down murderers but they can now detect harmful diseases as well. In recent developments in nanotechnology, the Israel Institute of Technology and the University of Pennsylvania (UPenn) have uncovered the power to detect whether someone has cancer through scent.
The human nose has about 5 million scent receptors, which we use to find everyday scents, but the average bloodhound has over 300 million. Based off this concept of an elevated scent, dog trainers at UPenn have trained their dogs at their Vet Center to detect tumors, cancers, infections, and predict future seizures with a very high success rate, some dogs even average a 100% detection rate in ovarian cancer. Unfortunately, not everyone can maintain a cancer-specialized dog and let alone train it in a location suitable to its nature.
Now we can create an artificial machine called the e-nose. Similar in name to e-skin, a tattoo-like nanotechnology to detect skin defects, the e-nose is a highly developed machine that mimics the nose of these special dogs. The machine has very tiny artificial DNA strands in which a carbon nanotube is attached. Those strands detect similar strands within the human body. The goal is to detect the scent of harmful diseased cells at the sensing rate of a dog. The patient can be evaluated in a multitude of ways, including through the bloodstream, urine, or saliva to detect VOCs, which are volatile organic compounds that can be used to detect certain cancers.
Researchers at the Israel Institute of Technology tested about 177 volunteers, some with and without cancer, to breathe into their version of an e-nose. The results from the nanosensor machine came out almost perfect. Not only did the sensor detect who had cancer but also what kind of cancer, and provided suggestions to how it could be treated.
“Physicians won’t just have one piece of information about the skin cancer but ideally several pieces of information from a compound that will provide a much more personalized look at the treatment options,” says Physics Professor Charlie Johnson at UPenn.
Melanoma, the deadliest form of skin cancer, is the main focus of the e-nose project at UPenn. Approximately 2.0% of all men and women will get melanoma at some point in their lifetime. The disease can only be detected, other than medical testing, by subtle changes in the skin, such as discoloration. Because of its subtleties it’s best to catch the cancer when it’s in its preliminary stages. This cancer gives off a certain odor that humans cannot detect, but dogs and the e-nose quickly can.
The e-nose is only a recent development in the medical field. The army, NASA and certain hospitals have been using specific e-noses to test for spoilage in foods and poison. But they cost thousands of dollars. How will scientists get this ability to locations all across the world?
UPenn researchers have seen the potential of their research dogs, even going as far as putting them on boats to track the location of killer whales. Humans have survived through the ages with their canine counterparts and through research are continuing to broaden the horizon of medically based technology. The current e-nose machines out on production are neither cost effective nor technologically advanced, but may someday have a meaningful impact to humans and the medical world.