Health sensors that attach directly to your organs to are potentially very useful, since they can measure miniscule electrical signals and other details that might otherwise fly under the radar. There's just one problem: actually sticking those devices on to something that soft and squishy is tough. However, a team of Japanese researchers may have a solution. They've developed gel-based sensors that monitor electrical activity and strain while adhering to just about anything, including the gooey wet insides of your body. The key is the gel itself, which is made of the polyvinyl alcohol you might find in protective gloves or eye drops; it allows a grid of sensors to make contact without peeling or slipping off.
Don't expect to carry one of these sensors on your body any time in the near future. The scientists are only just experimenting on living creatures, and it'll be a while before it's ready for human tests. However, there's a lot of potential. You could have advanced pacemakers that know the smallest details about your heart's palpitations, or plaster casts that make sure your limbs aren't under too much pressure. You might not love the idea of having electronics that are virtually inseparable from your body, but it would be considerably more elegant than the implants you'd otherwise have to use.
[Image credit: Sunwon Lee et. al.]