Work on growing organs is progressing smoothly, but slowly, thanks to the help of 3D printers. That same technology has now enabled scientists to create entire external body parts, like ears.

Phys.org reports that researchers at Princeton University have created a 3D printed ear made out of biogel. The ear contains a small antenna that’s able to pick up radio waves, and hear stereo sound when two are combined. What makes this particular feat more interesting is that the researchers were able to merge the electronic antenna with the biogel tissue in a way that’s at least somewhat natural.

“In general, there are mechanical and thermal challenges with interfacing electronic materials with biological materials,” said Michael McAlpine, an assistant professor of mechanical and aerospace engineering at Princeton and the lead researcher. “Previously, researchers have suggested some strategies to tailor the electronics so that this merger is less awkward. That typically happens between a 2D sheet of electronics and a surface of the tissue. However, our work suggests a new approach — to build and grow the biology up with the electronics synergistically and in a 3D interwoven format.”

This isn’t the first time that external body parts have been made with a 3D printer. Earlier this year, we brought you the story of the two designers that made a functioning hand for a boy born without one with the use of a 3D printer.

The difference between the two is that the hand was merely a prosthetic. Princeton’s bionic ear belongs to the rising trend of smart prosthetics, or artificial body parts that can replicate the function of the original. In this case, the electronics in the ear would allow one to hear again. It could also be used to enhance hearing by allowing humans to pick up radio signals without the use of additional hardware.

If you want to read more about Princeton’s research, check out the study at Nano Letters.

[Image: Frank Wojciechowski]