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Conducting Polymers in Neural Stimulation Applications

  • David D. Zhou
  • X. Tracy Cui
  • Amy Hines
  • Robert J. Greenberg
Chapter
Part of the Biological and Medical Physics, Biomedical Engineering book series (BIOMEDICAL)

Abstract

With advances in neural prostheses, the demand for high-resolution and site-specific stimulation is driving microelectrode research to develop electrodes that are much smaller in area and longer in lifetime. For such arrays, the choice of electrode material has become increasingly important. Currently, most neural stimulation devices use platinum, iridium oxide, or titanium nitride electrodes. Although those metal electrodes have low electrode impedance, high charge injection capability, and high corrosion resistance, the neural interface between solid metal and soft tissue has undesilable characteristics. Recently, several conducting polymers, also known as inherently conducting polymers (ICPs), have been explored as new electrode materials for neural interfaces. Polypyrrole (PPy), polyaniline (PANi), and poly(3,4-ethylenedioxythiophene) (PEDOT) polymers may offer the organic, improved bionic interface that is necessary to promote biocompatibility in neural stimulation applications. While conducting polymers hold much promise in biomedical applications, more research is needed to further understand the properties of these materials. Factors such as electrode impedance, polymer volume changes under electrical stimulation, charge injection capability, biocompatibility, and long-term stability are of significant importance and may pose as challenges in the future success of conducting polymers in biomedical applications.

This chapter looks into the current research and challenges for conducting polymers and their applications in neural stimulation electrodes.

Keywords

Charge Injection Electrode Impedance Electrochemical Polymerization PEDOT Film Neural Stimulation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • David D. Zhou
    • 1
  • X. Tracy Cui
    • 2
  • Amy Hines
    • 1
  • Robert J. Greenberg
    • 1
  1. 1.Second Sight Medical Products, Inc.SylmarUSA
  2. 2.Department of BioengineeringUniversity of PittsburghPittsburghUSA

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