Neuroengineers at MIT have created a implantable fuel cell that generates electricity from the glucose present in the cerebrospinal fluid that flows around your brain and spinal cord. In theory, this fuel cell could eventually drive low-power sensors and computers that decode your brain activity to interface with prosthetic limbs.
The glucose-powered fuel cell is crafted out of silicon and platinum, using standard semiconductor fabrication processes. The platinum acts as a catalyst, stripping electrons from glucose molecules, similar to how aerobic animal cells (such as our own) strip electrons from glucose with enzymes and oxygen. The glucose fuel cell products hundreds of microwatts (i.e. tenths of a milliwatt), which is a surprisingly large amount — it’s comparable to the solar cell on a calculator, for example. This should be more than enough power to drive complex computers — or perhaps more interestingly, trigger clusters of neurons in the brain. In theory, this glucose fuel cell will actually deprive your brain of some power, though in practice you probably won’t notice (or you might find yourself growing hungry sooner…)