Making electronic implants for the body is hard to do: tissue is delicate and stiff components can irritate it. Then there's getting those implants into the relevant organ without invasive surgery.
To help solve these problems, John A. Rogers, a materials science professor at the University of Illinois, and Michael Bruchas, an anesthesiologist at Washington University in St. Louis, built an electronic LED device so tiny it can be injected into delicate tissue, such as in the brain, without harming it. The experiment appears in this week's issue of the journal Science.
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Rogers told Discovery News that brain tissue is not only fragile, it also tends to move around because brains are suspended in fluid, and that creates problems when one tries to put relatively stiff, rigid electronics or fiber optics in place.
To get around this the researchers put together an extremely small circuit board with light-emitting diodes on it. The whole device is only about 25 microns thick. For comparison, a human hair is about 100 microns and fiber-optic cable strands are about 125. The thinness is part of what makes it so flexible.