clay has been researched along with hydroquinone* in 2 studies
2 other study(ies) available for clay and hydroquinone
| Article | Year |
|---|---|
Biosensor based on atemoya peroxidase immobilised on modified nanoclay for glyphosate biomonitoring.
A biosensor based on atemoya peroxidase immobilised on modified nanoclay was developed for the determination of glyphosate by the enzyme inhibition method. The inhibitor effect of the biocide results in a decrease in the current response of the hydroquinone that was used as a phenolic substrate to obtain the base signal. The biosensor was constructed using graphite powder, multiwalled carbon nanotubes, peroxidase immobilised on nanoclay and mineral oil. Square-wave voltammetry was utilised for the optimisation and application of the biosensor, and several parameters were investigated to determine the optimum experimental conditions. The best performance was obtained using a 0.1 mol L(-1) phosphate buffer solution (pH 7.0), 1.9×10(-4) mol L(-1) hydrogen peroxide, a frequency of 30 Hz, a pulse amplitude of 50 mV and a scan increment of 4 mV. The glyphosate concentration response was linear between 0.10 and 4.55 mg L(-1) with a detection limit of 30 μg L(-1). The average recovery of glyphosate from spiked water samples ranged from 94.9 to 108.9%. The biosensor remained stable for a period of eight weeks. Topics: Aluminum Silicates; Annonaceae; Biosensing Techniques; Buffers; Clay; Electrochemical Techniques; Electrodes; Enzymes, Immobilized; Glycine; Glyphosate; Graphite; Herbicides; Hydrogen-Ion Concentration; Hydroquinones; Limit of Detection; Mineral Oil; Nanotubes, Carbon; Peroxidase; Phosphates; Plant Proteins; Water Pollutants, Chemical | 2012 |
Light-harvesting energy transfer and subsequent electron transfer of cationic porphyrin complexes on clay surfaces.
A novel energy-transfer system involving nonaggregated cationic porphyrins adsorbed on an anionic-type clay surface and the electron-transfer reaction that occurs after light harvesting are described. In the clay-porphyrin complexes, photochemical energy transfer from excited singlet zinc porphyrins to free-base porphyrins proceeds. The photochemical electron-transfer reaction from an electron donor in solution (hydroquinone) to the adsorbed porphyrin in the excited singlet state was also examined. Because the electron-transfer rate from the hydroquinone to the excited singlet free-base porphyrin is larger than that to the excited singlet zinc porphyrin, we conclude that the energy transfer accelerates the overall electron-transfer reaction. Topics: Aluminum Silicates; Clay; Electron Transport; Electrons; Hydroquinones; Photochemistry; Porphyrins; Zinc | 2006 |