Gastronomic electronics: researchers create cheesy edible supercapacitors

What if your food could kill E. coli, or power a miniature camera inside your stomach? Researchers have developed a supercapacitor from food that can do just that — and it tastes like cheese, apparently.

Certain foods — cheese, egg white, seaweed, gelatin, barbecue sauce, Gatorade, gold leaf and activated charcoal, for instance — can store and conduct electricity. By combining several of these foods, researchers were able to create a supercapacitor.

From this supercapacitor, they created devices that kill E. coli, and are working on devices that wipe out other bacteria as well.

The supercapacitor was also able to power a camera designed to monitor the stomach.

“The main application is to pass through a (gastrointestinal) tract, doing whatever a GI doctor needs,” said Hanqing Jiang, an associate professor of mechanical engineering at the Arizona State University.

The device could replace endoscopies with real-time monitoring of the gastrointestinal tract. And the best part? It tastes like cheese, Jiang says.

 

Ingestible electronics aren’t a new concept, but previous devices haven’t been digestible, meaning that they need to be passed from the body. They can also cause issues if they break.

This creation, however, overcomes a number of problems previously faced by these types of devices. Implantable electronics, for instance, require surgery. Biodegradable electronics exist, but they have low energy density and battery size is limited. Edible materials proposed in the past contain toxic components that can cause stomach pain and nausea.

Jiang and his team took elements from the food industry, material sciences, device fabrication and biomedical engineering to create the supercapacitor. They used activated charcoal and gold for their high electrical conductivity and chemical stability.

While these devices were made by hand, in future they’ll be made by 3D printers and will be much smaller. (They are currently the size of a soy sauce packet.)

Jiang had trouble convincing the powers that be that his materials were for research, not for consumption.

“The funny thing is when we got all the materials in, I had a hard time getting reimbursed,” he said. “It was all food.”

The research was published in Advanced Materials Technologies.