Neurocompatible

Neurocompatible refers to materials, devices, or systems designed to interface with the nervous system in a way that minimizes adverse biological response and preserves neural function over time. The concept encompasses biocompatibility as well as mechanical and chemical compatibility with neural tissue, with the goal of reducing inflammation, fibrosis, and neuronal loss at the interface.

In practice, neurocompatibility covers neural implants and interfaces used for recording or stimulation, such as electrodes for deep brain stimulation, cochlear implants, and brain-computer interfaces, as well as less invasive sensors and drug-delivery systems that interact with neural circuits. Design considerations include reducing mechanical mismatch by using flexible, compliant materials with a low modulus similar to brain tissue, employing biocompatible polymers or coatings, and engineering surface properties to minimize scar tissue formation. Long-term stability, hermetic sealing, and wireless power and data transfer are also important aspects.

Common materials and approaches include platinum-iridium or carbon-based electrodes with insulating polymers, polymeric coatings such as parylene, and hydrogel interfaces. Researchers also explore biofunctional coatings and microstructures to promote neuron integration while discouraging glial encapsulation. Evaluation typically involves in vitro cytotoxicity assays and in vivo chronic implantation studies to assess impedance, signal quality, and tissue response.

Challenges remain in achieving truly chronic neurocompatibility, including micromotion-induced tissue injury, blood–brain barrier perturbation, and device degradation. Ethical and regulatory considerations, patient safety, and data privacy are also part of neurocompatibility assessment.