Modified microelectrode arrays

Nathan, Michael J. and Wrighton, Mark S., Chemically Modified Microelectrode Arrays. 37 391... 

Natan MJ, Wrighton MS. Chemically modified microelectrode arrays. Prog Inorg Chem... 

Preparation and Electrochemical Behavior of Microelectrodes Modified with Poly(I). A microelectrode array consisting of eight Pt microelectrodes is cleaned and platinized as described in the Experimental Section. Poly(I) is deposited on the platinized microelectrode array by scanning the potential of the electrode(s) from 0 V to 1.5 V vs. Ag+/Ag in a solution of 0.2 MX in CH3CN/O.I M [U-BU4N]PFg. The resulting array is illustrated in Scheme I. The... 

In this way a sonochemically fabricated microelectrode array was used to form an array of conducting microelectrodes [27] containing a genetically modified AChE which had been modified to maximise pesticide sensitivity. Use of an I125-labelled AChE meant that the amount of enzyme deposited could be measured and in this instance corresponded to 0.15 units activity. Measuring the amperometric... 

Okuno, 1., Maehashi, K., Kerman, K., Takamura, Y., Matsumoto, K., Tamiya, E. (2007b). Label-free immunosensor for pro state-specific antigen based on single-walled carbon nanotube array-modified microelectrodes. Biosens Bioelectron 22, 2377-2381. 

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. 

An electrochemically heterogeneous electrode is one where the electrochemical activity varies over the surface of the electrode. This broad classification encompasses a variety of electrode types [1, 2] including microelectrode arrays, partially blocked electrodes, electrodes made of composite materials, porous electrodes and electrodes modified with distributions of micro- and nanoscale electroactive particles. In this chapter, we extend the mathematical models developed in the previous chapter, in order to accurately simulate microelectrode arrays. Fbrther, we explore the applications of a number of niche experimental systems, including partially blocked electrodes, highly ordered pyrolytic graphite, etc., and develop simulation models for them. 

The electrochemical behavior of redox molecules in polymer films and gels has been investigated [4,7,18,23,61-66], but such behavior has usually been studied by using a modified electrode coated with a polymer film or gel in the presence of an outer electrolyte solution. In a few examples, entirely solid-state voltammetry was also achieved, but by using a microelectrode array [65,66] composed of working, counter, and reference electrodes because of the slow ionic or molecular diffusion in the soHd matrices. The apparent diffusion coefficient (Dapp) of a redox substrate in the films or solids coated on an electrode was very small [4,7,18,23,62-66], usually of the order of less than 10 cm s Another example of solid state votammetry is a report on the electrochemistry of Prussian blue in silica sol-gel electrolytes [67], but only Pt gauze working and counter electrodes for a - 1 mm-thick silica solid were used. Moreover, it is well known that solid electrolytes have been used on various sensors, electro chromic devices, etc. [68,69]. However, in spite... 

Salaun P, Josserand J, Morandini J, Girault HH, Buffle J (2004) Numerictil simulations of linear scan anodic stripping voltammetry at a modified squtire array of hemispherictil microelectrodes located in a thin-layer cell. J Electroemal Chem 566 147-158... 

Electrodes modified by electrodeposition of poly(3-methylthiophene) were used as chemical sensors of AA Multichannel electrochemical detection system fabricated using a 16-channel microelectrode array... 

Clay-modified electrodes with ruthenium purple Enzymic treatment with Cucumis sativus tissue which is a rich source of ascorbate oxidase Based on the quantitative electrolysis of AA A four-channel multipotentiostat for simultaneous measurements with microelectrode arrays. To reduce the complexity of electrochemistry cell, only one reference, and one auxiliary electrode are used Electrocatalytic determination of AA using tetraaza macrocycle-modified electrodes Neutralization of AA in ammonia leading to a change in conductivity... 

Abidian MR, Salas LG, Yazdan-Shahmorad A (2007) In-vivo Evaluation of Chronically Implanted Neural Microelectrode Arrays Modified with Poly (3,4-ethylenedioxythiophene) Nanotubes. Presented at Neural Engineering, 2007. CNE 07. 3rd International lEEE/EMBS... 

Porous electrodes, partially blocked electrodes, microelectrode arrays, electrodes made of composite materials, some modified electrodes and electrodes with adsorbed species are spatially heterogeneous in the electrochemical sense. The simulation of non-Cottrellian electrode responses at such surfaces is challenging both because of the surface variation and... 

Dubuisson E, Chibane A, Grangeat P, Mailley P (2009) Electrochemical DNA-hybridisation detection via enzymatic amplification at microelectrode array modified with polypyrrole-oligonucleotide films. Sens Lett 7(5) 880-887... 

PySSPy modified gold microelectrode arrays were used in this work. 

The modification of the Au electrode is similar to the procedure described by Taniguchi et al. . The electrode was dipped into a PySSPy solution (ca. 2 mM> for 10 min under a N2 atmosphere. The PySSPy modified Au microelectrode arrays are stable at the ionic strengths (1 mM - 200mM) and temperatures (3-55 C) used in this work. 

Figure 4. Linear sweep voltammograms (solid lines) at a PySSPy modified gold microelectrode array for the reduction of 44 pM cytochrome c in 0.2 M tris/cacodylic acid buffer at the scan rate of (a) 5 mVs , (b) 10 mVs i, (c) 20 mVs-, (d) 50 mVs i. cyclic voltammogram (dashed lines) at a PySSPy modified gold electrode with a large size (1.4 mm in diameter) was measured in the same solution for comparison.

Figure 7. Linear sweep voltammogram of cytochrome c at (a) PySSPy modified gold microelectrode array and (b) Tin doped In203 band microelectrode in 0.2 M ionic strength of tris/cacodylic acid buffer at scan rate of 10 mVs-. ...

---