Pacemakers work just fine. But logistically they're a nightmare: insertion is invasive, infections are common, and even if they're needed for only a short time, removal requires major surgery. But what if they and other medical devices like them could be replaced with microchip-size monitors that simply dissolved when they were no longer needed?
That's the idea behind transient electronics, a new medical technology being pioneered at Tufts, Northwestern and the University of Illinois at Urbana-Champaign. By making implantable devices out of biocompatible materials--think silicone, magnesium and silk--researchers are creating the ultimate medical aid: a wi-fi-enabled gadget that can dispense medication, monitor vitals and then dissolve on demand (via a wi-fi directive) or after a set period, without any kind of surgery. "It lifts an unnecessary load on the patient," says John Rogers of the University of Illinois, whose team helped develop the breakthrough technology.
Sound too good to be true? There are some caveats. Although the science is sound--the silicon-based chips are covered in magnesium, which naturally occurs in our bodies, and are coated with silk, which can be engineered to dissolve at a certain time--the FDA has yet to approve transient electronics, which Rogers estimates could take five to seven years. Moreover, there are safety concerns, as with any implant. "Will the immune system reject it? Is it causing a reaction?" he says. "There's a lot of groundwork that still needs to happen," including extensive testing in humans. Most of the researchers' findings come from experimenting on rats.
Still, the potential is massive. "Catheters, wires and tubes can all cause infections. It's a major problem," says Marvin Slepian, a researcher who teaches cardiology and bioengineering at the University of Arizona. Freed from worrying about those removal-surgery risks, doctors could use dissolvable sensors to measure temperatures, fight infections and more. "It's a lot better for the patient," says Slepian.
For now, though, Rogers' team is focused on perfecting the nascent technology by testing it on more animals and in different body parts and on finding enough low-cost and recycled manufacturing materials to make it affordable for the masses. "This is just the beginning of a new class of technology you're going to see in humans," he says.
Sources: Science; EPA