Microelectrode designs

Individual electrodes in an array may assume a disordered (random) or periodical arrangement. Random microelectrode arrays are characterized by a statistical distribution of electrodes that may be of identical or dissimilar dimension and shape. Ordered microelectrode arrays generally consist of an ensanble of electrodes of identical dimensions with a periodic arrangement. 

One of the first random miCToelectrode arrays reported consisted of sealing a bundle of individually conducting carbon fibers into epoxy (29). This array consisted of five layers of 20 electrodes where each electrode had a radius of 5 pm. Each disk was located at least six diameters from its nearest neighbor electrode so that diffusional cross-talk between 

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F. Bedioui, S. Trevin, and J. Devynck, Chemically modified microelectrodes designed for the electrochemical determination of nitric oxide in biological systems. Electroanalysis 8, 1085-1091 (1996). 

Marinesco, S. and Frey, O. (2013) Microelectrode designs for oxidase-based biosensors, in Neuromethods (eds S.Marinesco and N.Dale), vol. 80, Microelectrode Biosensors, pp. 3-25. 

Mercury electrodes have been reported for the detection of various metal ions. The sensitivity of MFE is better than HMDE because smaller volume of MFE leads to greater amount of the metal collected into mercury. With the microelectrode design covered with an antifouling agarose membrane, MFE is able to achieve excellent detection limit for Pb ", Cd ", and Cu " in seawater [57]. Due to the environmental issues faced by mercury electrodes, other material-based electrodes were also demonstrated. Carbon paste electrode... 

Buhrer, T., P. Gehrig, and W. Simon. 1988. Neutral-carrier-based ion-selective microelectrodes design... 

Marinesco S, Frey O (2013) Microelectrode designs fra- oxidase-based biosensors. NeuroMethods 80 3-25... 

Since the introduction of ion-selective electrodes with liquid ion-exchanger phases there are more possible microelectrode designs, as the fluid active phase can easily be placed in the tip of the capillary pipette electrodes usually employed in investigating biological cells. 

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