The Pre-clinical Safety of Graphene-based Electrodes Implanted on Rat Cerebral Cortex

Graphene has emerged as a promising nanomaterial for brain-computer interface (BCI) applications due to its excellent electrical properties and biocompatibility. However, its long-term structural compatibility on the cerebral cortex requires further validation. This study assessed both functional compatibility and preservation of neural tissue architecture for graphene/parylene C composite electrodes implanted on the rat cortical surface, in accordance with ISO 10993-6 guideline weekly neurobehavioral assessments and comprehensive histopathological analyses were conducted for four weeks post-implantation. Our results revealed no significant differences in neurobehavioral outcomes between graphene-based and medical-grade silicone implants. Histopathological examination showed no noticeable inflammatory responses, changes in cellular morphology, myelination status, or neuronal degeneration. These findings indicate that graphene electrodes preserve tissue integrity comparable to medical‑grade silicone. Our study supports graphene's potential use in clinical neuroprosthetics and neuromodulation devices.