Flexible Microelectrodes: Polymers & Applications

This lecture discusses polymer-based flexible microelectrodes for chronic neural implants, focusing on biocompatibility, flexibility, mechanical durability, and electrical insulation. Commonly used biopolymers like Parylene C, Polyimide, Polydimethylsiloxane (PDMS), and SU-8 are explored. Specific properties, processing techniques, and examples of polyimide-based and PDMS-based microelectrodes are presented. The lecture also covers cuff electrodes for sensory signal recording and muscle stimulation, as well as multichannel ECOG electrode arrays for brain function monitoring. Additionally, parylene-based microelectrodes, SU8-based microelectrodes, and multimodal microelectrode arrays with drug delivery and optical stimulation capabilities are discussed. The classification of peripheral nerve interfaces, electrode examples, and reliability issues related to tissue response and mechanical mismatch are also addressed.