Scientists have unveiled a see-through wrist cuff that measures the level of glucose in the bloodstream of diabetic patients and administers a drug to lower that level if needed. It’s not yet a full-blown treatment—for one thing, the experimental version can’t provide enough of the drug to do the trick—but it should be of great use in monitoring patients.

It’s also an actual application for a newfangled material in sore need of one: graphene, a superthin form of carbon with interesting electronic properties. By itself, graphene can’t sense glucose, but if you dope 2-D carbon properly, it can become quite a useful elecrochemistry set. The inventors—working in South Korea, Massachusetts and Texas—doped the graphene with minute quantities of gold to get the effect they wanted. They describe their work in this week’s issue of the journal Nature.

The idea of replacing the failing function of a diabetic pancreas dates even further back than the isolation of the critical pancreatic hormone insulin, in the 1920s. Before that, doctors had hoped to transplant the pancreas itself, or part of it,…[Read more]