‘Robotic nose’ more sensitive to smell than cancer-detecting dogs developed by scientists

Researchers are closer than ever to an artificial system that can detect disease with even greater sensitivity than canines, writes Tom Batchelor

A dog’s nose could hold the key to detecting cancers (PA)

From drug searches to disease detection, the powerful sense of smell that dogs enjoy is used by humans to solve everyday problems.

Now, researchers say they are closer than ever to creating an artificial “robotic dog nose” with even greater sensitivity than a canine, which could sniff out cancer and Covid-19.

Scientists from the Massachusettes Instutute of Technology (MIT) and several other universities and organisations said they had devised a system that can detect the chemical and microbial content of an air sample, enabling them to identify different diseases.

They hope the findings could lead to an automated odour-detection system small enough to fit inside a mobile phone.

“Dogs, for now 15 years or so, have been shown to be the earliest, most accurate disease detectors for anything that we've ever tried,” MIT researcher Andreas Mershin said.

”And now we've shown that we can do this. We've shown that what the dog does can be replicated to a certain extent.“

His team found that the dogs appeared able to respond to samples from patients with one type of cancer and identify several other types of cancer, even though the similarities between the samples weren't evident to humans.

Dr Claire Guest, chief scientific officer of Medical Detection Dogs, who led the study, said: “A dog's nose could hold the key to an urgently needed, more accurate, and non-invasive method of early prostate cancer diagnosis.

”Specialist-trained cancer detection dogs Florin and Midas detected extremely aggressive prostate cancers quickly and accurately from urine samples, even discriminating these against urine from patients that had other diseases of the prostate.

“This has enormous potential and in time the ability of the dogs' nose could be translated to an electronic device.”

A member of a bomb disposal squad from Gujarat Police walks with a sniffer dog to scan the field at Sardar Patel Gujarat Stadium, where India and England are scheduled to play their third test match in Ahmedabad, India (REUTERS)

Dogs boast such an impressive sense of smell because they have 300 million olfactory receptors in their noses. Humans have only around six million.

It means they can identify “cancers that don't have any identical biomolecular signatures in common”, said Mr Mershin.

”If you analyse the samples from, let's say, skin cancer and bladder cancer and breast cancer and lung cancer – all things that the dog has been shown to be able to detect – they have nothing in common.“

His team are working on a miniaturised detector system that incorporates those olfactory receptors and can be run using a typical smartphone.

The technology is said to be 200 times more sensitive than a dog's nose in terms of being able to detect and identify tiny traces of different molecules, but “100 per cent dumber” in terms of interpreting what the smells mean.

“When you smell a cup of coffee, you don't see a list of names and concentrations, you feel an integrated sensation,” Mr Mershin said. “That sensation of scent character is what the dogs can mine.”

One-Betta, a sniffer dog trained to detect the coronavirus disease, scans a library at the Florida International University in Miami (REUTERS)

During testing of 50 samples of urine from confirmed cases of prostate cancer, and samples known to be free of the disease, the artificial system was able to match four-year-old Labrador Florin and Midas, a seven-year-old Vizsla – with both the dogs and the “robotic nose” achieving a success rate of more than 70 per cent.

Such detectors could one day be used to pick up early signs of disease “years before a doctor notices”, said Mr Mershin, and could even be adapted to warn of smoke or a gas leak.

Mr Mershin said his interest in the study came during a study of bladder cancer detection when a dog repeatedly identified one member of the group as having the disease even though he had been confirmed as cancer-free by doctors.

The patient requested further tests after the dog’s reaction and was found to have the disease at a very early stage.

The findings, released in conjunction with UK-based Medical Detection Dogs, MIT, Johns Hopkins University, the Prostate Cancer Foundation and several other groups, were published in the journal PLOS One.