Conductive polymers are a fascinating category of materials that are particularly exciting for biomedicine because of their flexibility, conductivity, and biocompatibility. Existing conducting polymers, though, can only be applied to other materials using traditional methods that are not suitable for 3D printing.
Now, researchers at MIT have developed an impressive conducting polymer ink that can be used to print flexible volumetric devices to allow for close integration of electronics with the human body. As an example, the researchers were able to create a flexible neural probe that can sense the activity of neurons down to the resolution of individual cells. Traditional brain electrodes are made out of metals that tend to damage living cells that are nearby, and so can’t be used too invasively.
The new material can be printed together with other existing flexible materials in multi-material 3D processes, and it can be turned into a conductive soft hydrogel as well. The idea is that the softness of brain tissues requires a careful matching of the material to the task at hand, allowing for less damage to the brain while achieving high fidelity connectivity.
Here’s a snippet of the 3D printing of the conducting polymers:
Open access study in Nature Communications: 3D printing of conducting polymers