According to Michael McAlpine, an assistant professor of mechanical and aerospace engineering at Princeton, “In general, there are mechanical and thermal challenges with interfacing electronic materials with biological materials.” In the past, researchers have attempted to overcome this hurdle by binding a piece of “seed” tissue to an electronic component.
But at McAlpine’s lab, that un-artful solution is being challenged with new state of the art techniques. “[O]ur work suggests a new approach -- to build and grow the biology up with the electronics synergistically and in a 3D interwoven format."
To do this, the Princeton team used 3D printing to create the complex topography of the human ear with a matrix of hydrogel and calf cells. Silver nano particles, which made up the structure of the antenna, were added to the ear's form to create a new audio receiver.
Over the last few years, the researchers at Princeton have made a number of advances in this field and are now at the point where they can begin creating devices that not only replicate the form and function of the human ear but can extend its abilities to hear a wider range of the audio spectrum.
In a paper recently submitted to the journal Nano Letters, the group wrote, “"The design and implementation of bionic organs and devices that enhance human capabilities, known as cybernetics, has been an area of increasing scientific interest… This field has the potential to generate customized replacement parts for the human body, or even create organs containing capabilities beyond what human biology ordinarily provides."
While this technology won’t be available to patients anytime soon, McAlpine said that in principle the ear his team created could be used to replace a human’s ear and hearing.
Image courtesy of Frank Wojciechoski & Princeton University