Mark Ming-Cheng Cheng, an assistant professor from Wayne State University received a five-year, $475,000 grant from the National Science Foundation to study the potential of graphene for neural implants that can be used to treat disorders and diseases such as blindness, deafness, epilepsy, spinal cord injury, and Alzheimer's and Parkinson's. He hopes to check out whether graphene can be used to make reliable, high-performance, long-term implantable electrode systems.
Currently electrodes are used to stimulate connections between brain parts, but these typically stop working after a few weeks because scar tissue forms around the electrode, and the materials that comprise the electrode can't carry enough charge through the scar tissue. Cheng suggested that graphene might be better suited to long-term treatment than platinum and iridium oxide, two of the most popular materials now used to make implantable electrodes.
Graphene, he said, enables a larger electrical charge and can be made smaller than previous electrodes, yet still big enough to do the job. The smaller size and higher conductivity also decreases impedance, enabling clearer readings of neural activity, Cheng said. But graphene's flexibility actually makes it difficult to insert into tissue. Cheng plans to use a porous silicone "backbone" that slowly and safely biodegrades into brain tissue while releasing anti-inflammatory medication, thus limiting the formation of scar tissue.
