The electrochemical properties of Riboflavin adsorbed on carbon ionic liquid electrode (CILE) were studied by cyclic voltammetry. A film with a surface coverage of up to 3.3x10(-9) mol cm(-2) was formed after 10 min exposure time.
View Article and Find Full Text PDFA new sensor for the determination of mercury at microg ml(-1) levels is proposed based on the adsorption of mercury vapor on single-walled carbon nanotubes (SWCNTs). The changes in the impedance of SWCNTs were monitored upon adsorption of mercury vapor. The adsorption behaviour of mercury on SWCNTs was compared with that on multi-walled carbon nanotubes (MWCNTs) and carbon nanofibers (CNFs).
View Article and Find Full Text PDFDirect simultaneous electrochemical determination of glutathione (GSH) and glutathione disulfide (GSSG) has been presented using a nanoscale copper hydroxide carbon ionic liquid composite electrode. To the best of our knowledge, this is the first report on the simultaneous determination of these two biologically important compounds based on their direct electrochemical oxidation. Incorporation of copper(II) hydroxide nanostructures in the composite electrode results in complexation of Cu(II) with the thiol group of GSH and leads to a significant decrease in GSH oxidation overpotential, while an anodic peak corresponding to the direct oxidation of GSSG as the product of GSH oxidation is observed at higher overvoltages.
View Article and Find Full Text PDFThe effect of different substrates including stainless steel, activated carbon, single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), fullerenes (C60, C70, etc.) and SWCNTs doped with iron and palladium nanoparticles were compared for catalytic chemiluminescence reaction of sulfur compounds in a flame-containing cavity of molecular emission cavity analysis (MECA) system. Different forms of CNT substrates were fabricated using electric arc-discharge method.
View Article and Find Full Text PDFIncorporation of a phosphorylated ionic liquid as both a complexing and reducing agent for Pd(II) in a xerogel results in the formation of highly dispersed, uniformly sized Pd nanocatalysts, tightly supported on the surface of the silica and not embedded in the bulk of the xerogel.
View Article and Find Full Text PDFBiosens Bioelectron
February 2009
The direct electrocatalytic oxidation of glucose in alkaline medium at nanoscale nickel hydroxide modified carbon ionic liquid electrode (CILE) has been investigated. Enzyme free electro-oxidation of glucose have greatly been enhanced at nanoscale Ni(OH)(2) as a result of electrocatalytic effect of Ni(+2)/Ni(+3) redox couple. The sensitivity to glucose was evaluated as 202 microA mM(-1)cm(-2).
View Article and Find Full Text PDFThe electrocatalytic oxidation of sulfite was investigated at carbon ionic liquid electrode (CILE). This electrode is a very good alternative to previously described electrodes because the electrocatalytic effect is achieved without any electrode modification. Comparative experiments were carried out using carbon paste electrode (CPE) and glassy carbon electrode (GCE).
View Article and Find Full Text PDFIn this work arrays of palladium nanoparticles were synthesized on carbon ionic liquid electrode (CILE) (Pd/CILE), and the electrocatalytic oxidation of hydrazine was investigated using this electrode. Electrochemical oxidation of hydrazine in phosphate buffer (pH 7) was performed using cyclic voltammetry and square wave voltammetric techniques (SWV). Using the proposed electrode, a highly reproducible and well-defined peak was obtained for hydrazine at a very low potential of -0.
View Article and Find Full Text PDFA carbon ionic liquid electrode (CILE) was used for the investigation of the electrochemical oxidation of phenolic compounds in acidic media using cyclic voltammetry, chronoamperometry and square wave voltammetry techniques. The results indicate that, contrary to many other electrodes, the oxidation of phenolic compounds on CILE is highly stable and does not result in electrode fouling. Cyclic voltammetry showed that phenolic compounds such as phenol, 2,4-dichlorophenol and catechol were oxidized at CILE and remained electroactive after multiple cycles and at high concentrations of phenol.
View Article and Find Full Text PDFA recently constructed carbon composite electrode using room temperature ionic liquid as pasting binder was employed as a novel electrode for sensitive, simultaneous determination of dopamine (DA), ascorbic acid (AA), and uric acid (UA). The apparent reversibility and kinetics of the electrochemical reaction for DA, AA, and UA found were improved significantly compared to those obtained using a conventional carbon paste electrode. The results show that carbon ionic liquid electrode (CILE) reduces the overpotential of DA, AA, and UA oxidation, without showing any fouling effect due to the deposition of their oxidized products.
View Article and Find Full Text PDFIonic liquid, n-octylpyridinum hexafluorophosphate (OPFP) has been used to fabricate a new carbon composite electrode with very attractive electrochemical behavior. This type of carbon electrode has been constructed using graphite mixed with OPFP as the binder. The electrode has combined advantages of edge plane characteristics of carbon nanotubes and edge plane pyrolytic graphite electrodes together with the low cost of carbon paste electrodes and robustness of metallic electrodes.
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