Researchers print electronic tattoos directly onto the skin

While researchers have demonstrated electronic "tattoos" that can be applied to the skin, Duke University electrical engineers have shown that electronic components can be printed directly onto the body. Typically, printable electronics need post-processing to function but the Duke researchers used an aerosol jet printer to print silver nanowire ink at near room temperature and the circuits worked immediately. On the first try, the traces connected a battery to an LED that glowed. The skin circuits wash right off with soap and water. From IEEE Spectrum:

Flexible electronics are having a moment. The sheer range of devices developed recently demonstrates the scope and speed of the field, including patches to communicate with robots, wearables to reverse baldness or detect heartbeats, and solar cells that can be sewn into clothing....

In two recent papers, Franklin, Williams and colleagues at Duke demonstrate a low-temperature technique for printing electrical components—including leads and transistors—onto delicate surfaces such as apples, human skin and paper, with no post-processing required.

“Ultimately it doesn’t matter if it’s paper or plastic or what-not, you want to be able to put your surface in, add printed, functional electronics to that surface, and away you go,” says (electrical engineer Aaron) Franklin. The new technique enables researchers to print electronic components onto a wide range of materials and reduces overall production complexity and time, he says...

“We don’t want to just print conductive traces onto human skin,” says Franklin. “We want to actually show we can do a full printing on any surface with useful, functional biosensing devices.”

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New sensor pill like a "Fitbit" you can swallow to monitor your stomach

Researchers have developed a flexible sensor meant to be rolled up into a dissolvable capsule and swallowed so it can detect gastrointestinal problems and monitor food intake and digestion. The sensor is a 2 x 2.5 centimeter polymer that's printed with electronics, eventually to include wireless radio circuitry. Additional piezoelectric material enables the device to convert the movement from the stomach into enough electrical energy to power itself. The scientists from MIT and Brigham and Women’s Hospital tested a wired version of the device on pigs. From MIT News:

“For the first time, we showed that a flexible, piezoelectric device can stay in the stomach up to two days without any electrical or mechanical degradation,” (Canan) Dagdeviren says.

This type of sensor could make it easier to diagnose digestive disorders that impair motility of the digestive tract, which can result in difficulty swallowing, nausea, gas, or constipation.

Doctors could also use it to help measure the food intake of patients being treated for obesity. “Having a window into what an individual is actually ingesting at home is helpful, because sometimes it’s difficult for patients to really benchmark themselves and know how much is being consumed,” (Giovanni) Traverso says.

(via IEEE Spectrum)

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