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Corresponding Author

Zhou David(dmzhou@2-sight.com)

Abstract

Advances in biomedical engineering, micro-fabrication technology, and neuroscience have led to many novel and improved biomedical implants for electrical neural stimulation to restore human function and improve the quality of human life. Some examples of such biomedical devices are cochlear implants, visual implants, deep brain stimulators and spinal cord stimulators. One of the key components of biomedical implants is the stimulating electrodes. The electrodes, when in contact with living tissue, form an interface between the electronic device and the biological tissue. This paper reviews electrochemical aspects of neural stimulation implants. A brief introduction on the developments of biomedical implants is presented. The basis for electrical stimulation and the fundamental mechanisms of charge injection at the electrode/tissue interface are introduced. A survey of the most commonly used electrode materials and methods in the fabrication of microelectrodes is given. Some electrochemical related challenges for the development of medical implants, such as electrode reactions, impedance, charge injection capability, electrode corrosion and biocompatibility are discussed. In addition, microsensors and microbiosensors for possible applications in biomedical implants are reviewed. The challenges in the development of chronic implantable sensors for medical implants are also discussed. A better understanding of design issues and challenges may encourage interdisciplinary efforts including more contributions from electrochemists to push forward the development of neural stimulation biomedical implants.

Graphical Abstract

Keywords

neural stimulation, biomedical implants, electrode/tissue interface

Publication Date

2011-08-28

Online Available Date

2011-07-25

Revised Date

2011-07-11

Received Date

2011-06-07

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