Researchers at Massachusetts Institute of Technology have created a new complex multimodal fiber system that may be able to transmit drugs, light and electrical signals to the brain, according to a paper published in Nature Biotechnology.
Polina Anikeeva, PhD, professor in the Department of Materials Science and Engineering stated the fibers could ultimately be used for precision mapping of responses of different regions of the brain or spinal cord, resulting in a new type of neuroprosthesis.
Anikeeva and her team made use of a novel fiber-fabrication technology which creates polymers that can record multiple signals at once. The system of fibers could deliver optical signals and drugs directly to the brain, along with simultaneous electrical readout to continuously monitor the effects of various inputs.
The result, according to Anikeeva, is the fabrication of polymer fibers “that are soft and flexible and look more like natural nerves.” Devices currently used for neural recording and stimulation are made of metals, semiconductors, and glass, and can damage nearby tissues during ordinary movement.
“It is a big problem in neural prosthetics,” Anikeeva stated in a press release. “[Neuroprostheses] are so stiff, so sharp — when you take a step and the brain moves with respect to the device, you end up scrambling the tissue.”
The key to the technology is making a larger-scale version, called a preform, of the desired arrangement of channels within the fiber: optical waveguides to carry light, hollow tubes to carry drugs, and conductive electrodes to carry electrical signals. These polymer templates, which can have dimensions on the scale of inches, are then heated until they become soft, and drawn into a thin fiber, while retaining the exact arrangement of features within them.
The system can be tailored for a specific research or therapeutic application by creating the exact combination of channels needed for that task. “You can have a broad palette of devices,” Anikeeva stated.
Anikeeva P. Nature Biotechnology. 2015; doi:10.1038/nbt.3093.
Disclosure: The work was supported by the National Science Foundation, the Center for Materials Science and Engineering, the Center for Sensorimotor Neural Engineering, the McGovern Institute for Brain Research, the U.S. Army Research Office through the Institute for Soldier Nanotechnologies, and the Simons Foundation.