Nanotechnology Leading to Neural-Network-on-a-Chip Devices

Building the next generation of neural interfaces will require improving how axons are guided to create a “highway of nerve fibers” that can serve as an efficient passage of information. Nanowerk is reporting on research at Lund University in Sweden that uses free-standing nanowire patterns to potentially create neural networks on a chip.
From Nanowerk:

In new work that was recently published in Langmuir (Rectifying and Sorting of Regenerating Axons by Free-Standing Nanowire Patterns: A Highway for Nerve Fibers), the Swedish team shows that it is possible to impose a growth direction at a specific location on a substrate, something which is very important for neural chip construction for example.
Prinz [Christelle Prinz, a postdoc researcher in the Division of Solid State Physics at Lund University] explains that they have used a rectifier pattern made of arrays of short rows of electron beam lithography (EBL)-defined nanowires to sort axons coming from different places on a substrate. The short rows of nanowires are oriented at an angle of 30° compared to the growth direction. The arrays define highways for axonal growth, preventing the axons to turn around and change their growth direction.
"We not only show that patterns of nanowires can be used to rectify axonal outgrowth but we also demonstrate that axons from two different populations can be fully separated, thus creating the possibility to address two populations of axons on a chip surface," says Prinz. "These results, together with our earlier findings, provide a basis for the advanced control of neuronal growth on a chip, where a large range of functionalities can be implemented, including chemical sensors and electrodes to investigate neuronal function at high temporal and spatial resolution."

Read on at Nanowerk…
Abstract in Langmuir: Rectifying and Sorting of Regenerating Axons by Free-Standing Nanowire Patterns: A Highway for Nerve Fibers
Image: Confocal microscopy of bidirectionally rectified axonal outgrowth. (a) Nerve fibers from the green fluorescent protein (GFP)-expressing neurons from a ganglion mounted to the right. (b) The same image now showing the result of anti β-tubulin-labeled nerve fibers. The new (red) fibers originate from the wild-type ganglion mounted to the left. Because all fibers stain red, the GFP fibers now appear yellow. Scale bars 25 µm. Credit: American Chemical Society