If you have a certain kind of diabetes you already know this—getting a tiny bit of blood and then testing it for glucose is a daily ritual. People with diabetes have to test their blood a lot because if their blood sugar goes out of whack it can cause serious trouble and make them very sick.

New instruments to test blood glucose and make it less painful have been developed using some things from nanotechnology. Nanotechnology has also been used to build tiny pumps that deliver insulin, the molecule your body uses to control blood glucose. But wouldn’t it be neat if you didn’t have to prick yourself? What if there was some kind of gizmo that would automatically tell you what your blood glucose level was?

How about something cool like a…tattoo?

Scientists have been working on tattoos that instead of using ordinary ink use nanoparticles that can sense the level of glucose in your blood. These nanoparticles are made of a special polymer that is biocompatible and contains a molecule that fluoresces in the presence of glucose. Shine a light on the nano tattoo and it tells you how much glucose is in your blood.The tattoos are fluorescent so you can only see them under the special light. And that’s probably okay, since you don’t want to broadcast to your friends (and strangers) what’s going on with your body. There are still lots of things to be worked out, but the idea is neat and there are a lot of different kinds of tests that could be done with this sort of nanotechnology.