Graphene probe gives new insight into brain activity

Based on graphene field-effect transistors, the new device is capable of recording brain activity in high resolution while maintaining a strong signal to noise ratio (SNR). The work, published in the journal 2D Materials, brought together several Graphene Flagship partners from Germany and Spain, including TU Munich, the Spanish National Research Council (CSIC), and the Catalan Institute of Nanoscience and Nanotechnology (ICN2).

"Graphene is one of the few materials that allows recording in a transistor configuration and simultaneously complies with all other requirements for neural probes such as flexibility, biocompability and chemical stability,” said first author Benno Blaschke, from TU Munich.

“Although graphene is ideally suited for flexible electronics, it was a great challenge to transfer our fabrication process from rigid substrates to flexible ones. The next step is to optimise the wafer-scale fabrication process and improve device flexibility and stability."

The neural probes were used to record the large signals generated by pre-epileptic activity in rats, as well as the smaller levels of brain activity during sleep and in response to visual light stimulation. Neural activity is detected through the highly localised electric fields generated when neurons fire, so densely packed, ultra-small measuring devices are required for accurate brain readings.