Glucose-monitoring nanodevice is only skin deep

The science of the very small may deliver a new technology that can constantly monitor a person's blood sugar level and alert them when they need an insulin shot. The nanosensors would be injected under the skin, much like dye for a tattoo. Rising glucose levels in the blood would trigger a fluorescent response under an infrared light, alerting a patient if they need a shot after a meal. And the same nanosensor could be used to detect and track levels of other chemicals, such as sodium, which could be used to detect dehydration.

Heather Clark and her team of scientists at Draper Laboratory in Cambridge, MA want to fine tune the technology so that the sensors can be regularly added just under the skin, allowing them to be regularly sloughed off rather than remain permanently. They're using 120-nanometer polymer beads that contain sensor molecules and a dye.

"It's unique because it doesn't have any components to be used up," Clark tells MIT Technology Review. "Glucose strips, for example, use an enzyme to detect glucose, which needs to be continually replaced. Other monitors, even nanosensors, have a limited lifetime, which makes implanting them difficult."

Currently, diabetics use a blood test to determine glucose levels. So far, animal tests have failed to detect an immune response, which could alter the way the sensors work. And researchers say they'll be watching closely for such adverse reactions as they near the clinic.

- read the report from MIT Technology Review