There are a variety of situations that may call for the implantation of electrodes in the brain, ranging from the treatment of neurological conditions to possibly even restoring the function of paralyzed limbs. A newly-developed hydrogel could someday replace such electrodes, allowing for better functionality.

Conventional electrodes used in neural interfaces are typically made of rigid metals such as gold or platinum. Because these don't match the soft consistency of neural tissue, they're usually coated with a flexible conductive polymer. Unfortunately, though, this increases their size, making them more obtrusive within the brain.

With that in mind, scientists from Spain's University of the Basque Country collaborated with colleagues at France's University of Strasbourg to create the experimental new biopolymer hydrogel. The gel itself is starch-based, but contains graphene to make it highly electrically-conductive.

Ordinarily, graphene isn't stable within aqueous materials such as the hydrogel. That problem was overcome with the addition of stabilizing extracts from the salvia plant. As an added bonus, those extracts have anti-inflammatory and antibacterial properties.

While small pieces of the hydrogel could one day serve as a soft, flexible alternative to the currently-used metal electrodes, the scientists note that much more research and development will be required in the meantime.

A paper on the research was recently published in the journal Carbohydrate Polymers.