Assessment of PGA coated Polyimide Microelectrode as a Flexible, Implantable Neural Interface for CNS

Neuroprosthetic devices have been suggested as part of a Brain Machine Interface (BMI) intended to restore functionality in humans affected with various sensory or motor function losses. The longevity of such implantable devices is increasingly becoming a limiting factor in successfully developing and delivering neuroprosthetic systems suitable for clinical use. One factor implicated in the long-term failure of implanted devices is the relative rigidity of the devices with respect to the softer mechanical property of the human brain. To alleviate these concerns, polymer-based devices have been suggested as an alternative to more traditional, silicon-based micromachined devices. The objective of this research is to develop such polyimide based electrode array suitable for the specific application of restoring hearing in deaf patients. The work on the manufacturing, electrochemical evaluation, acute animal recording and implantation techniques of the polyimide-based flexible recording electrodes, designed for rat auditory cortex, is discussed. Specifically, application of poly (glycolic acid) (PGA) to temporarily enhance the device stiffness of the flexible polyimide devices is discussed in the scope of the thesis. The temporary enhancement of the device stiffness is to minimize the brain damage during the insertion of the device into the brain.