The brain is responsible for regulating life sustaining functions, taking in sensory information, controlling movement, and creating thought. All of this is accomplished by electrical impulses running through elaborate networks of neurons in a way that is poorly understood. Now, a team of researchers led by Bozhi Tian (2016) has created microscopic nanowires that can be inserted into neurons and hit with light to produce electrical impulses and provides a way for researchers to better understand how electrical signals work in the brain. The nanowires are made with two types of silicon that create a small electrical current when hit by light, and the electrochemical reactions are catalyzed by gold diffused onto the wires. Both silicon and gold are biologically compatible materials, making them safe for implantation, and would naturally degrade in a couple of months. The nanowires themselves are so small that hundreds of them could sit side by side on the edge of a sheet of paper. When the nanowire is illuminated with light, the voltage difference between the inside and outside of the cell is slightly reduced and lowers the barrier for the neuron to fire an electrical signal to another neighboring neuron. Tian and his team tested the nanowires on lab-grown rat neurons and were able to successfully trigger the neurons to fire using light. Tian next plans to test the nanowires in animals. The nanowires promise a way to better understand electrical signaling in the brain by studying electrical impulses in individual nerve cells and may lead to possible therapeutics for nerve pain, Parkinson’s disease, or psychiatric disorders.
- Photoelectrochemical Modulation of Neuronal Activity With Free-Standing Coaxial Silicon Nanowires. Parameswaran R, Carvalho-de-Souza JL, Jiang Y, Burke MJ, Zimmerman JF, Koehler K, Phillips AW, Yi J, Adams EJ, Bezanilla F, Tian B. Nature Nanotechnology. 2018 Feb 19. doi: 10.1038/s41565-017-0041-7.
In the News
- Researchers Invent Tiny, Light-Powered Wires to Modulate Brain's Electrical Signals (link is external)
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