Electrode Nafion-modified

Y.-M. Zhou, Z.-Y. Wu, G.-L. Shen, and R.-Q. Yu, An amperometric immunosensor based on Nafion-modified electrode for the determination of Schistosoma japonicum antibody. Sensors and Actuators, B Chemical 89, 292-298 (2003). 

Research was done with redox systems incorporated into Nafion-modified electrodes because of interesting possible applications of such systems, e.g., for electron-transfer catalysis. 

Nafion modified electrodes (Section 57.3.2.1) have been shown to promote electrogenerated chemiluminescence from the [Ru(bipy)3]2+/oxalate system.44 The problem of the quenching of the eel by water was overcome in the Nafion case since sections of the electrode coating were hydro-phobic. However, aqueous systems continue to be of interest in the development of practical eel devices such as digital display units (see also Section 57.3.2.5(iv)). It has been shown that eel is... 

I. Luiz de Mattos and M. Carneiro da Cunha Areias, Automated determination of glucose in soluble coffee using Prussian Blue-glucose ox-idase-Nafion modified electrode, Talanta, 66(5) (2005) 1281-1286. 

Le Gal La Salle, A. Limoges, B. Rapicault, S. Degrand, C. Brossier, P. New immunoassay techniques using Nafion-modified electrodes and cationic redox labels or enzyme labels. Anal. Chim. Acta 1995, 311, 301-308. 

However, Nafion-modified electrodes also exhibited several disadvantages. For example, the response time of the Nafion-coated sensors increases due to a reduced diffusion coefficient value in the film [7], This can pose a serious disadvantage for in vivo work where dopamine and other neurotransmitter releases often occur on a sub-second time scale. In addition, Nafion coatings perform well for applications such as stripping analysis, but their use for direct voltammetric analysis is complicated by slow equilibration of the film with solution species [5 7], Therefore, there is a need for a modification system that can allow for rapid and selective permeation of the ions of interest. 

L. Kavan and M. Gratzel, Nafion modified Ti02 electrodes Photoresponse and sensitization by Ru(II)-bipyridyl compounds, Electrochim. Acta, 1989, 34, 1327— 1334. 

Enzyme-like behavior was observed for electrocatalyt-ic oxidation on Nafion/lead-ruthenium oxide pyrochlore chemically modified electrodes.Nafion is loaded with lead(II) and ruthenium(III) cations by ion exchange, and then their oxides are prepared by in situ precipitation in such a way that the catalytically active sites remain... 

N. Zhu et al [32] reported in 2005 the use of Pt-NPs combined with nafion-solubilized MWCNTs as electrode-surface modifiers for fabricating sensitivity-enhanced electrochemical DNA biosensor. The hybridization events were monitored by DPV measurements of the intercalated daunomycin (Fig. 5.5). Due to the ability of MWCNTs to promote electron-transfer reactions and the high... 

Liu, Y, Yuan, R., et al. Direct electrochemistry of horseradish peroxidase immobilized on gold coUoid/cysteine/nafion-modified platinum disk electrode. Sensors and Actuators B Chemical, 15(1), 109-115 (2006). 

Au, or Cu) (PDPA, Nafion) (modified electrode) CNTs—conducting component Nobie metai—cataiyst... 

Oxalate Fibre optic based sensor Ru(bpy)3 + immobhized on a Nafion modified electrode Urine, vegetables 3X10-5 M (179) (Continued)... 

Disposable TCNQ-Nafion modified screen-printed electrode coupled to differential pulse voltammetry (DPV)[12] and... 

In this article, we describe the preparation and use of amperometric electrodes for sensing the analytically significant substrate glucose based on a PEG-modified glucose oxidase (GOD) (4,5) and on a lipid-modified GOD (6). The PEG-modified GOD has been incorporated into a carbon paste (CP) electrode the modified enzyme exhibits higher activity in a hydrophobic CP matrix than hydrophilic, native GOD (7-10). The lipid-modified GOD has been immobilized on a glassy carbon (GC) electrode with a thin Nafion overcoat. The water-insoluble modified enzyme is far more stable between the electrode surface and the polymer layer than native GOD (77). 

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