Continuous glucose monitors (CGMs) have saved a lot of people from pricking their fingers several times a day. They are still far from perfect, and cost a lot. A team at Texas A&M University thinks it has a cheaper and simpler alternative. In a study published in ACS Measurement Science Au, the researchers describe a sensor small enough to inject under your skin.
Why do current glucose monitors still feel like a chore?
A typical CGM has a thin sensor under your skin and a patch on top holding it in place. You swap it out every 5 to 14 days, and the adhesive can leave your skin red and itchy over time. Many models also need calibration with finger-prick readings, which defeats part of the purpose. A single sensor costs anywhere from about $60 to $180, and without decent insurance, that bill keeps coming back.
So, how does a glowing sugar molecule measure glucose?
The Texas A&M sensor doesn’t use enzymes at all. It relies on a protein that latches onto sugar and a near-infrared dye attached to a sugar molecule. When your glucose climbs, glucose kicks the dye-tagged molecule loose, and its glow changes. Near-infrared light travels through skin well, so a reader outside your body could pick up the signal without any electronics inside the implant. The researchers also believe it could work regardless of your skin tone.
What I like most is the focus on cost. The team chose a sugar molecule called beta-mannopentaose, which is roughly 10 times cheaper than the version it was compared against, and it held up just as well. In lab tests, it tracked glucose between 25 and 400 mg/dL, which covers low, normal, and high readings.
All of this fits inside a hydrogel rod about 2.5mm wide and 11mm long, designed to be injected under the skin. After seven days, the rod still held more than 94% of the glowing sugar molecule.
When can you actually get one?
Nobody can say yet. The sensor has only been tested in the lab, and the researchers still have to show it works reliably inside the body for long stretches. If they pull it off, a patch-free monitor at a fraction of today’s price would make a real difference for the more than 500 million people living with diabetes.
