Nafion coating

NADH, 121, 122, 180 Nafion coating, 118, 123, 124, 126 Nanometer electrodes, 116, 128 Nernst equation, 3, 15, 80 Nernstian behavior, 143 Nernst Planck equation, 5 Neuronal sensors, 188 Neurotransmitters, 40, 116, 124 Neutral carrier electrodes, 154 Nickel, 123... 

Figure 10.10 Temperature dependence of H2O2 yield F(H202) at Nafion-Pt(4.8 nm)/CB (O), Nafion—Pt(2.6nm)/CB (A), Nafion—Pt(1.6 nm)/CB (O ), Nafion-Pt(2.6nm)/CB with the same Pt loading as 1.6 nm catalyst ( ), Nafion-Pt(bulk) ( ), and Pt(bulk) without Nafion coating (v)- t m = 50cms (From Yano et al. [2006b], reproduced by permission of the PCCP Owner Societies.)...

Yano H, Higuchi E, Uchida H, Watanabe M. 2006a. Temperature dependence of oxygen reduction activity at Nafion-coated bulk Pt and Pt/carbon black catalysts. J Phys Chem B 110 16544-16549. 

Photocatalytic oxidation of ethanol on Pt/ri02 and Nafion coated Ti02 catalysts were studied using in situ infrared IR techniques. Infrared studies show that the reaction produced acetaldehyde, acetic acid, acetate, formic acid, formate, and CO2/H2O. Modification of the Ti02 catalyst by Pt and Nafion slowed down the oxidation reaction through site blocking. Incorporation of Pt was found to favor formation of formate (HCOO ), indicating Pt decreases the rate of oxidation of formate more than that of its formation. 

Jacobs, A. Dahlman, O. Enhancement of the quality of MALDI mass spectra of highly acidic oligosaccharides by using a Nafion-coated probe. Anal. Chem. 2001, 73,405 110. 

J. Hayon, D. Ozer, J. Rishpon, and A. Bettelheim, Spectroscopic and electrochemical response to nitrogen monoxide of a cationic iron porphyrin immobilized in nafion-coated electrodes or membranes. J. Chem. Soc.-Chem. Commun. 619-620 (1994). 

E.V. Gogol, G.A. Evtugyn, J.L. Marty, H.C. Budnikov, and V.G. Winter, Amperometric biosensors based on Nafion coated screen-printed electrodes for the determination of cholinesterase inhibitors. Talanta 53, 379-389 (2000). 

Another study compared the bulk gold electrode to Nafion coated gold electrodes using RRDE in 0.5 M H2S04. There were no significant differences observed in the reaction pathway or kinetics of ORR on the electrodes.213... 

Because Nafion film can preconcentrate organic cations at a substrate electrode surface, Nafion-coated electrodes can be used as sensitive and selective sensors for electroactive organic cations. The film-entrapped ion is then either oxidized or reduced and the resulting current is recorded and related to the concentration of ions in the aqueous solution (qualitatively similar to anodic stripping voltammetry). It was shown that ion-exchange voltammetric determination of the dication methyl viologen at a Nafion-film-coated electrode results in an improvement of three orders of magnitude in detection limit relative to an uncoated electrode.46... 

Figure 1.19 SEM image ofthe Pt/Fe(lll) cooperative composites immobilized on a Nafion-coated GCE. (Reprinted with permission from Ref [74], 2004 Elsevier.)...

An improved adsorption of DNA bases has been observed at a chemically modified electrode based on a Nafion/ruthenium oxide pyrochlore (Pb2Ru2-x FhxOj-y modified GC (CME). Nafion is a polyanionic perfiuorosulfonated ionomer with selective permeability due to accumulation of large hydrophobic cations rather than small hydrophilic ones. The Nafion coating was demonstrated to improve the accumulation of DNA bases, while the ruthenium oxide pyrochlore proved to have electrocatalytic effects towards the oxidation of G and A. The inherent catalytic activity of the CME results from the Nafion-bound oxide surface being hydrated. The catalytically active centers are the hydrated surface-boimd oxy-metal groups which act as binding centers for substrates [50]. 

The electrochemical behavior of [Ru(tpy)(bpy)(OHA] + in aqueous solution and when incorporated in Nafion coatings has been studied in detail. ... 

A. J. Cunningham and J. B. Justice, Jr., Approaches to Voltammetric and Chromatographic Monitoring of Neurochemicals in Vivo, J. Chem. Ed. 1987, 64, A34. Another Nafion-coated electrode can detect 10 10 mol of the neurotransmitter nitric oxide within a single cell [T. Malinski and Z. Taha, Nitric Oxide Release from a Single Cell Measured in Situ by a Porphyrinic-Based Microsensor, Nature 1992, 358, 676]. 

Fig. 9.18 Effect of nafion-coating on Ti02 in the degradation of the herbicide paraquat.

Human chorionic gonadotrophin (hCG) Competitive immunoassay on Nafion-coated SPCEs in microwells DPV oxidation of accumulated cationic product of substrate hydrolysis by ALP enzyme Scan from Oto +0.7V 200-10,000 mlUmP1 100 mlU (lmg= 9825 IU) Bagel et al. [75]... 

Addition of PCR-amplified virus DNA to Nafion-coated SPCEs in microwells... 

Capelo, S., Mota, A.M. and Gongalves, M.L.S. (1995) Complexation of lead with humic matter by stripping voltammetry. Prevention of adsorption with Nafion-coated mercury film electrode. Electroanalysis, 7, 563-568. 

Bjorklund Blom, L., G.M. Morrison, M.S. Rauch, G. Mills, and R. Greenwood. 2003. Metal diffusion properties of a Nafion-coated porous membrane in an aquatic passive sampler system. J. Environ. Monit. 5 404-409. 

Gerhardt GA, Oke AF, Nagy G, Moghaddam B, Adams RN (1984) Nafion-coated electrodes with high selectivity for CNS electrochemistry. Brain Res 290(2) 390-395. 

Gerhardt GA, Hoffman AF (2001) Effects of recording media composition on the responses of Nafion-coated carbon fiber microelectrodes measured using high-speed chronoamperometry. J Neurosci Methods 709(1) 13-21. 

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