Thorsten Graunke adjusted the laser just as a swab from a Parkinson’s patient arrived from Dresden’s university clinic—no blood, no scan, just a simple wipe from the nose. What happened next could change how we catch diseases early. Using a highly sensitive laser system, Graunke and his team at the Fraunhofer Institute for Integrated Circuits IIS detected invisible chemical clues in body odor that distinguish people with Parkinson’s disease, COVID-19, and other illnesses from healthy individuals.
Our bodies constantly release volatile organic compounds (VOCs)—tiny molecules in our breath, sweat, and skin that make up our unique scent. When disease strikes, this scent subtly changes. For years, scientists have known that conditions like Parkinson’s alter body odor, sometimes detectable even by smell. But now, instead of relying on human noses, researchers are using precision lasers to read these changes like a barcode.
The team, working with the Technical University of Dresden, collected swabs from the nasal cavity, navel, and outer ear of 24 volunteers—six healthy individuals and six each with Parkinson’s, COVID-19, or other conditions. The nasal swabs worked best. Placed into a custom-built device, each sample was hit with mid-infrared laser light. When the light hits VOCs, it creates faint sound waves picked up by an ultra-sensitive detector—a technique called photoacoustic spectroscopy. The result? A unique chemical fingerprint for each person.
Even more surprising, follow-up tests on three Parkinson’s patients two weeks later showed consistent results, suggesting the signal is stable over time. The method doesn’t replace diagnosis, but it could flag who needs closer testing—fast. And because the data showed they could reduce the range of wavelengths needed, the team believes a compact, low-cost version could one day be used in clinics or even pharmacies.
This isn’t science fiction. The study, published in Scientific Reports, proves that disease-related odors can be measured objectively and accurately with lasers. While larger, real-world trials are still needed, the door is now open for non-invasive, rapid screening tools that could catch diseases earlier, with nothing more than a swab and a beam of light.