Bioelectric devices

Noble metal connections can reduce the corrosion to an "acceptable" level. This assumption is not true for leads which enter the package from sensors such as micro-electrodes which are characterized by relatively high impedances. The trend for neuroprosthe-tio devices is towards closed-loop control in which the use of high impedance bioelectric sensors will be common. In addition, differing potentials within multi-circuit cables can result in corrosion even when the conductors are fabricated from highly corrosion resistant materials such as MP35N. 

Good overviews of biopotential electrodes are found in Geddes L. A. 1972. Electrodes and the Measurement of Bioelectric Events, New York, John Wiley 8c Sons and Ferris C.D. 1974. Introduction to Bioelectrodes, New York, Rlenum. Even though these references are more than 20 years old, they clearly cover the field, and httle has changed since these books were written. Overviews of biopotential electrodes are found in chapters of two works edited by John Webster. Chapter 5 of his textbook. Medical Instrumentation Application and Design, covers the material of this chapter in more detail, and there is a section on bioelectrodes in the Encyclopedia of Medical Devices and Instrumentation... 

Poly(chloro-p-xylylene) is suitable for its use in implantable, microfabricated devices [83]. It is hydro-phobic, with a low dielectric constant, and a good biocompatibility. However, for many bioelectrical applications, its poor wet adhesion may be a drawback. 

Kutz, M ed. 2009. Biomedical Engineering and Design Handbook. New York McGraw-Hill. This one-volume work focuses on human biomechanics, biomaterials, and bioelectricity, then segues into design principles for medical devices, imaging systems, and prostheses. 

Keywords Bioelectric phenomena BioFET BioLED Biomolecular electronics OFET OLED Organic electronics Photonic devices Plastic electronics... 

E. Palmqvist, C. Berggren Kriz, M. Khayyami, B. Danielsson, P- O. Larsson, K. Mos-bach, D, Kriz, Development of a simple detector for microbial metabolism, based on a polypyrrole resistometric device. Biosens. Bioelectr., 1994,9, pp. 551-556. 

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