A novel device that that emits electromagnetic waves and then reads and interprets the signals reflected back from tissue and blood vessels was able to accurately track blood sugar levels, researchers report. The device uses two sensors situated in different spots on the body to generate the data that is translated into blood sugar readings, according to the report published in Science Advances. "This work represents the first of a kind noninvasive continuous wearable glucose monitoring technique," said study coauthor Joseph Constantine, an associate professor in the department of electrical and computer engineering at the Maroun Semaan Faculty of Engineering and Architecture at the American University of Beirut. "A non-invasive continuous system will allow us to follow closely on glycemic variations leading to better and more comfortable diabetes management. Checking your glucose level becomes as simple as checking your phone." The prototype included sensors in a glove and a wristband. The sensors were designed to mirror the blood vessel anatomy in the hand and wrist, which allowed alignment of the sensors with the blood vessels, improving the sensitivity of the device. "Wireless electromagnetic waves propagate through the human tissue to reach the bloodstream," Constantine explained in an email. "If the composition of the blood changes due to variation in glucose levels then the wave characteristics vary." "More precisely, the changes in the reflected and/or transmitted waves, in terms of magnitude and phase shifts, are associated with glucose fluctuations in the medium under test," Constantine said. "The physical characteristics of the reflected and/or transmitted waves are processed and converted into glucose levels by means of data analytics and smart algorithms." To validate their needle-less continuous monitoring system, the researchers recruited 21 healthy volunteers who were asked to wear the devices while undergoing three separate oral glucose tolerance tests. The actual glucose measurements were highly correlated with the device's readings, without any time lag, Constantine and his colleagues report. The device's sensors are not limited to use in a glove and a wrist band, but can be placed in other wearable accessories, Constantine said. "For example, a glove and an arm-band can be used by a sports-person, a sock by a child, and a necklace by an adult on an outing," he added. "In the future we envision integrating similar sensors in various types of apparel which vary in size." The new prototype is just the beginning, Constantine said. "We believe this is the first step towards pain-free glucose monitoring and diabetes management while providing more freedom and flexibility to diabetic patients of all ages," he added. The study is "interesting and a good proof of principle," said Dr. David Lam, an assistant professor at the Icahn School of Medicine at Mount Sinai and medical director of the clinical diabetes institute for the Mount Sinai Health System, in New York City. "The more we can have less-invasive technology provide accurate information on someone's blood glucose the better it is for patients and clinicians," Dr. Lam said. "There is a large group of patients who have a big aversion to needles. This would be a needle-less way to provide glucose information." With that said, the device needs to be tested with a wide range of glucose levels, Dr. Lam added. "Most sensors have pretty good accuracy in the middle ranges. But it's in the extremes that is where the error can start to get greater." Source
