Gummy Bears Can Now Detect Voltage Changes


Scientists have 3D printed microelectrode array on gummy bears, which allows them to detect voltage changes resulting from activity in neurons or muscle cells

Researchers from TUM and Forschungszentrum Jülich have teamed up to perform inkjet printing onto a gummy bear. They have printed microelectrode array comprising of a large number of electrodes to detect signals produced by muscle cells, onto the chewy candy.

Making prototype using inkjet printer

Instead of attaching printed electrodes on soft materials, scientists have directly printed electrodes on soft materials using carbon-based ink.  To prevent the sensors from picking up stray signals, they added a neutral protective layer to the carbon paths.

“If you instead print the electrodes, you can produce a prototype relatively quickly and cheaply. The same applies if you need to rework it,” says Bernhard Wolfrum, Professor of Neuroelectronics at TUM. “Rapid prototyping of this kind enables us to work in entirely new ways,” he added.

Through experiments with cell cultures, the team has confirmed that these sensors provide reliable measurements. With an average width of 30 micrometers, they also permit measurements on a single cell or just a few cells. This is difficult to achieve even with established printing methods.

Potential applications

Microelectrode arrays printed on soft materials could be used in many different areas. They are appropriate not only for rapid prototyping in research but could also change the way patients are treated.

“In the future, similar soft structures could be used to monitor nerve or heart functions in the body, for example, or even serve as a pacemaker,” says Prof. Wolfrum. At present, he and his team is working to print more complex three-dimensional microelectrode arrays. They are also studying printable sensors that react selectively to chemical substances and not only to voltage fluctuations.

Microelectrode are there for a very long time now, but in their original form, they consist of hard materials such as silicon. This causes several disadvantages when they come into contact with living cells as they can trigger inflammation and several other problems. These all can be avoided by using soft materials in electronics for healthcare.