The development of ultrathin and flexible electrodes for neural recordings is reported in a study published online this week in Nature Materials. Such electrodes could be used as a less invasive tool in neuroscience research and emerging clinical applications including brain-controlled prostheses.

A key challenge in brain research is the recording of electrical signals from targeted groups of neurons over long periods of time. The microelectrodes that are typically used for this purpose are rigid and comparatively large, and can damage surrounding tissue during implantation and wear. Takashi Kozai, Daryl Kipke, Nick Kotov and colleagues fabricate biocompatible composite electrodes from flexible carbon nanofibres that are protected with a protein-resistant coating and carry conducting polymer recording pads. The probes are ten times thinner than established silicon electrodes, more compliant with brain tissue and are shown to record neural signals in rats over several weeks.