Brazilian researchers have developed a novel sensor capable of detecting early signs of Parkinson's disease by analyzing human tears. This innovative method, which delivers results in approximately three minutes, is presented as a faster, more affordable, and less invasive alternative to current blood tests used for measuring dopamine levels.
Dopamine levels typically decrease in individuals with Parkinson's disease a decade before the onset of physical symptoms such as tremors. Early detection is therefore critical, according to Mark Frasier, chief scientist at the Michael J. Fox Foundation for Parkinson's Research. The tear sensor, the product of a five-year development effort by researchers at the Federal University of Pelotas, has the potential to identify this decline years before a patient becomes aware of any issues.
"This technology of measuring dopamine and tears could be really valuable, early, and even before symptoms developed to identify someone that has lower dopamine, that may be at risk for developing the symptoms of Parkinson's disease," Frasier stated.
Lead researcher Lucas Gonçalves and his supervisor Neftalí Carreño explained that while doctors monitor dopamine levels to assess Parkinson's risk, the standard approach involves blood draws, which are costly and require repeat testing. Their sensor, however, requires only a single tear sample.
"Blood tests are very expensive, very invasive, and always you need to do one more time," Gonçalves said. "In this case, we can take a tear, put in the sensor and do it quickly, three minutes maybe, for the results."
The sensor is constructed from electrically conductive graphene, which generates a signal upon interaction with dopamine. In the researchers' study, dopamine was introduced to synthetic tears, and the sensor successfully identified levels consistent with those observed in Parkinson's patients.
Carreño described the process as both simple and rapid. The research team envisions a future where this sensor could be commercialized and adapted into a compact, at-home kit, available for purchase at pharmacies much like glucose monitoring devices for individuals with diabetes.
Having accessible at-home testing could significantly aid in the early identification of Parkinson's disease, empowering individuals to monitor their dopamine levels proactively. Although Parkinson's disease is not typically a direct cause of death, it can lead to fatal complications over time.
"In the future, it is possible, because you can take this information that you collect in your house very quickly for the hospital, for your doctor and take action," Carreño added.