Injection of electronics
Neurophysiologists have learned how to inject electronics into the brain using a syringe
A set of flexible electronics is able to connect to nerve cells without harm to their health — to monitor their condition or even influence them (for the treatment of Parkinson's disease, for example). The new technology is reported in the journal Nature Nanotechnology (Jia Liu et al., Syringe-injectable electronics).
A picture from an article in the Harvard University newspaper
Injectable device delivers nano-view of the brain – VM.
Understanding how the activity of individual neurons leads to higher forms of nervous activity (perception, thinking, emotions) is the most important problem of neurophysiology. From the point of view of technology, its solution requires devices that monitor thousands and millions of cells at the same time. However, modern implants are difficult to inject into the brain, and their electrodes are perceived as an alien body and cause irritation. Eventually, the devices become overgrown with tissues and isolated from neurons.
Chemist Charles Lieber from Harvard removed these obstacles by developing a three-dimensional grid made of an alloy of chromium and platinum, together with a polymer coating to protect the electrodes from corrosion. The mesh is flexible enough to fit into a thin syringe needle. After entering the brain, the grid of 16 electronic components returns to its original shape. It consists of 90 percent of voids: thanks to this, brain cells perceive it as a neutral framework and are freely placed in it. During the five weeks of experiments, no increased immune reaction to the mesh was noticed — the brain does not perceive it as a foreign body.
Schematic representation of Lieber's experiments
Picture: Lieber Research Group / Harvard University
The scientists conducted their experiments on mice placed under anesthesia. They managed to monitor individual neurons and stimulate them. After the injection, 90 percent of the devices worked successfully.
At the next stage, Lieber plans to implant large grids of hundreds of electronic components, and monitor the activity of neurons in the brains of awake individuals. To do this, you will either have to fix their heads, or create new wireless communication technologies to track the neurons of freely moving animals. In addition, scientists are going to introduce the device into the brains of newborn mice: as they grow, the grid will unfold, capturing more and more neurons.
However, the new technology can find application not only in neurophysiology and medicine: Lieber also introduced meshes into various synthetic materials (for example, voids in silicone rubber). The injected electronics can also be useful for monitoring the condition of buildings and bridges by introducing corrosion and pressure sensors into the cavities.
Portal "Eternal youth" http://vechnayamolodost.ru11.06.2015