Neural microelectrodes

Microelectrode neural probes facilitate the functional stimulation or recording of neurons in the central nervous system and peripheral nervous system. Minimizing the electrode impedance is an important requirement for obtaining high quaKty signals (high signal-to-noise ratio). It has been shown [59,60] that... 

What is the nature of these messenger chemicals, which are detected by the use of microelectrodes so small that they can sense the chemicals emitted from a single cell In view of what has been said earlier about the large size of proteins, the messenger chemicals are relatively small. For example, acetylcholine is a vital part of the neural transport system in mammals. Its structure is... 

At present a few studies of nanofibers and nanombes are focused on CNS drug delivery. One study evaluated electrospun nanofibers of a degradable polymer, PLGA, loaded with antiinflammatory agent, dexamethasone, for neural prosthetic applications (Abidian and Martin, 2005). A conducting polymer, poly(3,4-ethylenedioxythiophene), was deposited to the nano-fiber surface and the coated nanofibers were then mounted on the microfabricated neural microelectrodes, which were implanted into brain. The drug was released by electrical stimulation that induced a local dilation of the coat and increased permeability. 

Microelectrodes made of carbon have been used for in vivo neuroelectrochemistry to measure catecholamines in neural tissues [137]. A major technical issue is distinguishing one compound from another using redox potential as a basis and differential pulse voltammetry as the method. 

Pizzi R, Cino G, Gelain F, Rossetti D, Vescovi A (2007) Learning in human neural networks on microelectrode arrays. Biosystems 88(1-2) 1-15... 

Y. Chen, C. Guo, L. Lim, S. Cheong, Q. Zhang, K. Tang and J. Reboud, Compact microelectrode array system Tool for in situ monitoring of drag effects on nemotransmitter release from neural cells. Analytical Chemistry, 80(4), 1133-1140 (2008). 

Kovacs G T A et al 1994 Silicon-substrate microelectrode arrays for parallel recording of neural activity in peripheral and cranial nerves IEEE Trans. Biomed. Eng. BME-41 561-71... 

Hoogerwerf, A.C. and Wise, K.D. A three-dimensional microelectrode array for chronic neural recording. IEEE Trans. Biomed. Eng. 41 1136-1146. 

J.Y. Yang and D.C. Martin, Microporous conducting polymers on neural microelectrode arrays -1 - Electrochemical deposition. Sens. Actual. B Chem., 101(1-2), 133-142 (2004). 

Maintenance of contact with neural cells is integral to the performance of the implant device and the use of biosynthetic CP coatings will potentially improve the long-term efficacy of such devices. Limited research is available on the long-term interactions of CPs with neural tissue. Two studies by the Martin research group at Michigan University have examined the chronic performance of nanostructured PEDOT on neural recording electrodes [52,144]. The microelectrode arrays coated with surfactant-templated PEDOT and... 

Y. Xiao, X. Cui, and D.C. Martin, Electrochemical polymerization and properties of pedot/s-edot on neural microelectrode arrays, J. Electroanal. Chem., 573, 43-48 (2004). 

K.A. Ludwig, J.D. Uram, J. Yang, and D.C. Martin, Chronic neural recordings using silicon microelectrode arrays electrochemicaUy deposited with poly(3,4-ehtylenediox3fthiophene) (pedot) film, J. Neural Eng., 3, 59-70 (2006). 

M.R. Abidian and D.C. Martin, Experimental and theoretical characterization of implantable neural microelectrodes modified with conducting polymer nanotubes. Biomaterials, 29(9), 1273 1283 (2008). 

X. Cui and D.C. Martin, Electrochemical deposition and characterization of poly(3,4-ethyle-nedioxythiophene) on neural microelectrode arrays. Sens. Actuat. B Chem., 89(1-2), 92-102 (2003). 

M.R. Abidian, L.G. Salas, A. Yazdan-Shahmorad, T.C. Marzullo, D.C. Martin, and D.R. Kipke. In-vivo evaluation of chronically implanted neural microelectrode arrays modified with poly (3,4-ethylenedioxythiophene) nanotubes. In Proceedings of the 3rd International IEEE EMBS Conference on Neural Engineering Kohala Coast, Hawaii, USA, 2007. 

Deng, M., Yang, X., Silke, M., Qiu, W., Xu, M., Boi s, G., and Chen, H. (2011]. Electrochemical deposition of potypyrrole/graphene oxide composite on microelectrodes towards tuning the electrochemical properties of neural probes. Sens. Actuators S Chem., 158, pp. 176-184. 

Keywords Cochlear implants (CFs) Microelectrode material Neural stimulation and sensing Titanium Nitride (TiN)... 

The requirements for microelectrode materials used in CTs and neural implants is increasing nowadays for achieving high performance and stability in their dedicated applications. The microelectrode material selection is an key factor for the success of such implants. Here in this section we talk about the microelectrode material requirements with the charge transfer techniques between the electrode material and the electrolyte. 

Williams, J. C., Rennaker, R. L., and Kipke, D. R. (1999), Long-term neural recording characteristics of wire microelectrode arrays implanted in cerebral cortex. Brain Res. Brain Res. Protoc. 4(3) 303-313. 

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