A team at the Massachusetts Institute of Technology (MIT) has developed a noninvasive device for measuring blood glucose levels, potentially offering an alternative to traditional finger-prick tests for diabetes patients.
The new technology uses Raman spectroscopy, which analyzes how near-infrared or visible light interacts with tissue to reveal its chemical composition. The researchers created a shoebox-sized device that can measure blood glucose without the need for needles.
In trials involving a healthy volunteer, the device produced measurements comparable to those from commercial continuous glucose monitoring sensors that require subcutaneous wire implants. Although the current version is too large to be worn, the team has since designed a wearable prototype now being tested in a small clinical study.
Arianna Bresci, an MIT postdoctoral researcher and lead author of the study published in Analytical Chemistry, explained: "By refraining from acquiring the whole spectrum, which has a lot of redundant information, we go down to three bands selected from about 1,000. With this new approach, we can change the components commonly used in Raman-based devices, and save space, time and cost."
Traditional methods for monitoring blood glucose involve either drawing blood for glucometer testing or using wearable monitors inserted under the skin. These options can cause discomfort or skin irritation and require frequent replacement.
Researchers at MIT’s Laser Biomedical Research Center (LBRC) have been working on noninvasive alternatives based on Raman spectroscopy. Earlier attempts could only indirectly estimate glucose levels by comparing signals from interstitial fluid with reference blood measurements. More recently, however, they achieved direct measurement of glucose signals by adjusting how light is shone onto and collected from the skin.
The latest study reduced equipment size by focusing on just three specific spectral bands related to molecular features of interest rather than analyzing all 1,000 typically present in a Raman spectrum. This allowed them to build a more compact and affordable device.
During clinical testing at MIT's Center for Clinical Translation Research (CCTR), researchers monitored changes in blood glucose over four hours as a subject consumed two high-glucose drinks. Measurements were taken every five minutes using their new device and compared favorably with two invasive commercial monitors.
Following these results, MIT researchers have developed an even smaller prototype—about the size of an iPhone—which is currently being tested as a wearable monitor among healthy and prediabetic volunteers at CCTR. Plans are underway for larger studies involving people with diabetes next year in collaboration with local hospitals.
Efforts continue to further reduce device size—potentially down to watch dimensions—and ensure accuracy across different skin tones.
Funding support came from the National Institutes of Health, Korea’s Technology and Information Promotion Agency for SMEs, and Apollon Inc., a biotechnology company based in South Korea.
