Scientists at Lund University are developing implantable bio-friendly electrodes capable of capturing signals from single neurons in the brain over an extended period of time.
According to a news release obtained by EurekAlert, there are several factors that must be considered for the electrodes to successfully record neuronal signals from the brain with decisive results. First, the electrode must be bio-friendly and cannot cause any significant damage to the brain tissue. Second, the electrode should be flexible in relation to the brain tissue.
“Remember, the brain floats in fluid inside the skull and moves around when we, for instance, breathe or turn our heads,” says Professor Jens Schouenborg who leads the project together with Dr. Lina Pettersson. “[That is why] the electrode and the implantation technology that we have now developed have these properties, which is unique.”
Indeed, the 3-D electrodes are extremely soft and flexible, so much so that they actually deflect against a water surface. A hard but dissolvable gelatine material is used to encapsulate the electrodes for implementation. Essentially, this allows the electrodes to be retained in their original form when inside the brain, enabling them to monitor neural activity.
It should be noted that flexible electrodes have traditionally been incapable of maintaining their shape when implanted, causing them to rub against and irritate the brain tissue, which leads to dead nerve cells around the electrode.
“The signals then become misleading or completely non-existent,” explains Johan Agorelius, a doctoral student in the project. “Our new technology enables us to implant as flexible electrodes as we want and retain the exact shape of the electrode within the brain.”
As Schouenborg notes, the bio-friendly implantable electrodes being developed by Lund researchers creates entirely new conditions for understanding what happens inside the brain. This could lead to more effective treatments for diseases such as Parkinson’s and chronic pain conditions.
Rambus Fellow and Research Director Dr. David Stork expressed similar sentiments.
“The work from Lund University addresses a difficult problem — that of keeping electrodes aligned with target brain neurons despite inevitable motion and flexion of the brain in moving animals,” he told Rambus Press. “This approach will surely reduce some of the sources of rejection of neural implants. It will be fascinating to see how the approach works someday in human trials. Only in careful trials will the team learn whether this new class of flexible microelectrodes will overcome the problems of penetration of the blood-brain barrier that have plagued many earlier approaches.”