Determination of Trace Metals by Differential Pulse Voltammetry at Chitosan Modified Electrodes

Abstract

The inhibition of copper corrosion in 3.5% NaCl solution has been studied at 25 o C using three inhibitors: 1-phenyl-2,4-dithiobiuret(Inh I), 1-p-methoxyphenyl-2,4-dithiobiuret(Inh II) and 1-p-chlorophenyl-2,4-dithiobiuret(Inh III). The inhibition efficiencies of these compounds have been evaluated by weight loss and electrochemical methods (impedance spectroscopy and polarisation curves). The surface study was done by using SEM and ESCA techniques. The inhibition efficiencies of the inhibitors follow the sequence Inh II > Inh I > Inh III. The inhibitors Inh I, Inh II and Inh III appear to inhibit corrosion process through the formation of a protective film which was found to consist of Cu(I)-inhibitor complex, cuprous chloride CuCl or CuCl 2 -complex ions or both on the surface. .

Effect of electropolymerisation conditions on the permeability of polyphenol films deposited on a vitreous carbon electrode

“…(3), from curve 2 in is equal to 184%; this value, higher than 100%, suggests that the film permeability for phenate anion is governed by the preferential partitioning of the probe into the polyphenol film due to stronger interactions (electrostatic, hydrophobic, etc.) in the film than in the solution [24].…”

“…, expressed as a percentage, is defined as the ratio of the oxidation peak current intensity during the 1st scan at the polyphenol film-coated electrode I film over that at the bare electrode I bare [23,24]:…”

Water treatment: Chitosan associated with electrochemical methods

“…However, electrodes modified with chitosan nanotubes are still little explored. Martí nezHuitle et al (2010) developed a research modifying vitreous carbon electrode with chitosan [39]. According to the proposed study, it was used to determine trace metals (Cu, Pb, Cd, Co, As and Pt) in aqueous solutions.…”

Current Frontiers in Electrochemical Biosensors Using Chitosan Nanocomposites

“…The permeability properties of the chitosan surface fi lms for cationic [Ru(NH 3 ) 6 3 + ] and anionic [Fe(CN) 6 4 − ] species at different pH was investigated. It was observed that the electrochemical response was strongly pH -dependent for both ionic species and by changing the concentration of chitosan solution, a charge -based molecular recognition of ionic species was made possible [20] . In a different study, peroxidase isozyme ( POX1B ) entrapment within chitosan cross -linked with glyoxal resulted in good immobilization and activity levels, and good enzyme stability at high temperature and during storage.…”