导电高分子在神经界面电极中的应用

As a medium of information communication between human body and external devices, neural interface electrode provides an effective tool for people to further explore the working mechanism of nervous system. Most of the traditional nerve electrodes are made from metal or semiconductor materials. These materials have become the main preparation materials of early nerve electrode because of their inert material characteristics and excellent electrical conductivity. However, due to the mechanical mismatch caused by excessive rigidity and smooth surface, and the high electrochemical impedance with biological tissues, these materials limit the further development of nerve electrode. As an organic conductive material, conductive polymer has the characteristics of softness(Young's modulus is about 0.01-10 GPa) and conductivity(the conductivity of highly doped conductive polymer is in the metal range of 10⁰-10⁵ S/cm), which is an effective material for nerve electrode preparation. In recent years, conductive polymers have been used to modify or even replace the traditional electrode materials to reduce the interface impedance and improve the sensitivity of electrode detection; At the same time, it can increase the stability of electrode implanted in vivo for a long time by reducing the strain mismatch between the electrode and tissue, the inflammatory reaction, and further introducing functional biomacromolecules into the conductive polymer to reduce the rejection of biological tissue to the electrode. In this paper, we will discuss and summarize the application of conductive polymer materials in neural electrode. Herein, three aspects of conducting polymer, including polymer coating nerve electrode, all polymer neural electrode and conductive polymer composite material neural electrode, are discussed respectively. The application prospect and existing problems of conductive polymer in neural interface electrode are analyzed, which can provide reference for the further development of neural interface electrode in brain science, bioelectronic medicine and other frontier fields.