One of the key difficulties with all bio-implants is rejection by the body. Traditionally, rejection had to be fought with relatively powerful immuno-suppressant drugs that tended to have severe side-effects. A lot of effort has gone into finding less problematic ways of reducing rejection, and this new study using nanotechnology is promising:

The new brain implants developed at the University of Michigan are coated with nanotubes made of a biocompatible and electrically conductive polymer that has been shown to record neural signals better than conventional metal electrodes.

“Microelectrodes implanted in the brain are increasingly being used to treat neurological disorders,” says Mohammad Reza Abidian, a postdoctoral researcher in Michigan’s Neural Engineering Laboratory. “Conducting polymers are biocompatible and have both electronic and ionic conductivity. Therefore, these materials are good candidates for biomedical applications such as neural interfaces, biosensors and drug delivery systems.”

[Reference: Futurity: University of Michigan]