Flexible and Soft Materials and Devices for Neural Interface

Abstract

AbstractThe stability of the interface between neural tissue and chronically implanted devices is crucial for interrogation for both the central and peripheral nervous systems. One of the main challenges of chronic implants is the degradation of recording and stimulation performance over time. This is partly due to the inflammatory host tissue responses to the implanted devices, resulting in decreased density and health of neuronal elements at the electrode vicinity and scar encapsulation. In the last decade, a significant effort has been made in the development of devices that have subcellular features and/or made with soft, flexible, and stretchable materials. These strategies can trigger less foreign body response and improve the integration of the implanted device and neural tissue. In this chapter, we will discuss the most recent strategies adopted to tune the structural, functional, and dimensional properties of materials with the aim to match the mechanical, chemical, and electrical properties of the nervous system. We will discuss these strategies applied to different components of an implanted device from insulation substrate and conductive electrode materials to soft tethers and modulus-matching coatings.KeywordsSoft materialFlexible electronicsNeural interfacesBiodegradable materialsConductive polymerHydrogelsBiodegradable materialsCarbonPenetrating electrodesμECoG arraysNerve electrodes