In the future it is expected that it will be possible to insert nanoscale electrodes to study learning and memory functions and to treat patients suffering from chronic pain, depression, and diseases such as Parkinson's. But it is not known what would happen if the nanoelectrodes would break away from their contact points.
Scientists at Lund University in Sweden have investigated this 'worst case by injecting nanowires in rat brains. The nanowires resemble in size and shape the registration nodes of electrodes of the future. The results show that the brain 'clean-up cells' (microglia), take care of the wires. After twelve weeks only minor differences were observed between the brains of the test group and the control group.
"The results indicate that this is a feasible avenue to pursue in the future. Now we have a better base on which to develop more advanced and more useful electrodes than those we have today," explains Christelle Prinz, a scientist in Solid State Physics at the Faculty of Engineering (LTH).
Electrodes are already used today to counteract symptoms of Parkinson's disease, for instance. Future nanotechnology may enable refined and enhanced treatment and pave the way for entirely new applications.
One advantage of nanoscale electrodes is that they can register and stimulate the tiniest components of the brain. To study the biological safety - the biocompatibility - of these electrodes, the scientists first produced nanowires that were then mixed into a fluid that was injected into the rat brains. An equal number of rats were given the solution without the nanowires. After 1, 6, and 12 weeks, respectively, the researchers looked at how the rat brains were reacting to the nanowires.
"Together with other findings and given that the number of microglial cells decreased over time, our results indicate that the brain was not damaged or chronically injured by the nanowires," Christelle Prinz concludes.
MEDICA.de; Source: The Swedish Research Council