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Charlotte B Braungardt - One of the best experts on this subject based on the ideXlab platform.
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Cathodic Stripping Voltammetry
Encyclopedia of Analytical Science, 2005Co-Authors: Eric P Achterberg, José L. Barriada, Charlotte B BraungardtAbstract:Cathodic Stripping Voltammetry (CSV) is an analytical technique used for the analysis of low levels of analytes (principally trace metals and sulfur containing organic compounds) in aqueous solutions, and is based on the measurement of a reductive current response as a function of a potential scan towards more negative potentials. The technique is highly sensitive (limits of detection of 10− 10–10− 12 mol l− 1) because of the application of a preconcentrations step prior to the Stripping step. During the preconcentration the analyte is collected on the surface of the working electrode (typically a mercury drop), often in the presence of an added electro-active ligand. The CSV technique has been used for automated measurements of trace metals in marine waters, but a key strength of CSV is in its use in trace metal speciation measurements in natural waters, in particular dissolved iron in marine waters.
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Stripping Voltammetry for the determination of trace metal speciation and in situ measurements of trace metal distributions in marine waters
Analytica Chimica Acta, 1999Co-Authors: Eric P Achterberg, Charlotte B BraungardtAbstract:Progress in marine chemistry has been driven by improved sampling and sample handling techniques, and developments in analytical chemistry. Consequently, during the last 20 years our understanding of marine trace metal biogeochemistry has improved a great deal. Stripping voltammetric techniques (anodic Stripping Voltammetry and adsorptive cathodic Stripping Voltammetry) have made an important contribution to this understanding. The selectivity and extremely low detection limits have made Stripping Voltammetry a widely used technique for trace metal speciation and trace metal distribution measurements in seawater. Stripping Voltammetry is very suitable for ship-board and in-situ applications because of the portability, low cost and capability for automation of the voltammetric instrumentation. Future developments in Stripping Voltammetry can be expected in the field of stand-alone submersible voltammetric analysers, capable of continuous trace metal measurements. Future applications of Stripping Voltammetry can be found in the interactions between trace metal speciation and growth and the functioning of organisms in pristine and metal polluted marine waters.
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Stripping Voltammetry for the determination of trace metal speciation and in-situ measurements of trace metal distributions in marine waters
Analytica Chimica Acta, 1999Co-Authors: Eric P Achterberg, Charlotte B BraungardtAbstract:Progress in marine chemistry has been driven by improved sampling and sample handling techniques, and developments in analytical chemistry. Consequently, during the last 20 years our understanding of marine trace metal biogeochemistry has improved a great deal. Stripping voltammetric techniques (anodic Stripping Voltammetry and adsorptive cathodic Stripping Voltammetry) have made an important contribution to this understanding. The selectivity and extremely low detection limits have made Stripping Voltammetry a widely used technique for trace metal speciation and trace metal distribution measurements in seawater. Stripping Voltammetry is very suitable for ship-board and in-situ applications because of the portability, low cost and capability for automation of the voltammetric instrumentation. Future developments in Stripping Voltammetry can be expected in the field of stand-alone submersible voltammetric analysers, capable of continuous trace metal measurements. Future applications of Stripping Voltammetry can be found in the interactions between trace metal speciation and growth and the functioning of organisms in pristine and metal polluted marine waters. Copyright (C) 1999 Elsevier Science B.V
Richard G. Compton - One of the best experts on this subject based on the ideXlab platform.
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Optimising carbon electrode materials for adsorptive Stripping Voltammetry
Applied Materials Today, 2017Co-Authors: Korbua Chaisiwamongkhol, Christopher Batchelor-mcauley, Stanislav V. Sokolov, Jennifer Holter, Neil P. Young, Richard G. ComptonAbstract:Abstract Different types of carbon electrode materials for adsorptive Stripping Voltammetry are studied through the use of cyclic Voltammetry. Capsaicin is utilised as a model compound for adsorptive Stripping Voltammetry using unmodified and modified basal plane pyrolytic graphite (BPPG) electrodes modified with multi-walled carbon nanotubes, carbon black or graphene nanoplatelets, screen printed carbon electrodes (SPE), carbon nanotube modified screen printed electrodes, and carbon paste electrodes. We compare the analytical performance of the different electrodes in terms of sensitivity and limit of detection, concluding that carbon electrodes modified with high surface area material exhibit an improvement of sensitivity. In terms of limit of detection, increasing the electrode surface area however does not improve the detection limit; the limit of detection is similar for all electrodes studied.
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Absorptive Stripping Voltammetry for cannabis detection.
Chemistry Central journal, 2015Co-Authors: Rita Nissim, Richard G. ComptonAbstract:Given that Δ9-tetrahydrocannabinol, the active constituent of cannabis, has been shown to greatly reduce driving ability, thus being linked to many drug driving accidents, its reliable detection is of great importance. An optimised carbon paste electrode, fabricated from graphite powder and mineral oil, is utilised for the sensitive detection of Δ9-tetrahydrocannabinol (THC) in both aqueous solutions of pH 10.0 and in synthetic saliva solutions. “Absorptive Stripping Voltammetry” is exploited to that effect and the paste is used to pre-concentrate the carbon paste electrode with the target molecule. Practical limits of detection of 0.50 μM and 0.10 μM are determined for THC in stationary and stirred aqueous borate buffer solutions, respectively. Theoretical limits of detection are also calculated; values of 0.48 nM and 0.41 nM are determined for stationary and stirred THC aqueous borate buffer solutions, respectively. THC concentrations as low as 0.50 μM are detected in synthetic saliva solutions. The sensitivity of the sensor was 0.12 μA μM−1, 0.84 μA μM−1 and 0.067 μA μM−1 for the stationary buffer, the stirred buffer and the saliva matrix, respectively. “Absorptive Stripping Voltammetry” can be reliably applied to the detection of Δ9-tetrahydrocannabinol, after suitable optimisation of the assay. Usefully low practical limits of detection can be achieved.
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anodic Stripping Voltammetry of silver nanoparticles aggregation leads to incomplete Stripping
ChemistryOpen, 2015Co-Authors: Samantha J Cloake, Her Shuang Toh, Patricia T Lee, Chris Salter, C Johnston, Richard G. ComptonAbstract:The influence of nanoparticle aggregation on anodic Stripping Voltammetry is reported. Dopamine-capped silver nanoparticles were chosen as a model system, and melamine was used to induce aggregation in the nanoparticles. Through the anodic Stripping of the silver nanoparticles that were aggregated to different extents, it was found that the peak area of the oxidative signal corresponding to the Stripping of silver to silver(I) ions decreases with increasing aggregation. Aggregation causes incomplete Stripping of the silver nanoparticles. Two possible mechanisms of ‘partial oxidation’ and ‘inactivation’ of the nanoparticles are proposed to account for this finding. Aggregation effects must be considered when anodic Stripping Voltammetry is used for nanoparticle detection and quantification. Hence, drop casting, which is known to lead to aggregation, is not encouraged for preparing electrodes for analytical purposes.
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Influence of Electrode Roughness on Stripping Voltammetry: Mathematical Modeling and Numerical Simulation
The Journal of Physical Chemistry C, 2009Co-Authors: Denis Menshykau, Richard G. ComptonAbstract:Electrodes with rough surfaces inevitably have practical importance from both applied and fundamental points of view including electroanalysis where Stripping Voltammetry is a popular technique due to its simplicity and high sensitivity. The diffusional domain approach is used to model Stripping Voltammetry at rough electrodes: two models of the electrode surface, “rough” and “scratched”, are considered. Electron transfer is described by three models which correspond to cases of Stripping of a monolayer, a thin layer, and a bulk layer. The shape of the votammograms strongly depends on the model of the electron transfer but is not always sensitive to the precise model of the electrode surface; the conditions under which this is the case are identified, and generic roughness effects on Stripping Voltammetry are quantified. We conclude that electrode roughness can have a significant effect on the Stripping of the metals from the solid electrode especially in respect of the voltammetric waveshape.
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The Stripping Voltammetry of Hemispherical Deposits Under Electrochemically Irreversible Conditions: A Comparison of the Stripping Voltammetry of Bismuth on Boron-Doped Diamond and Au(111) Electrodes
The Journal of Physical Chemistry C, 2009Co-Authors: Sarah E. Ward Jones, Kathryn E. Toghill, Susan H. Zheng, Sylvie Morin, Richard G. ComptonAbstract:A study of the Stripping Voltammetry of hemispherical deposits under electrochemically irreversible conditions is presented. Experiments show a difference in the Stripping Voltammetry of bismuth from a single crystal Au(111) electrode where the bismuth covers the surface in relatively flat film and a boron-doped diamond (BDD) electrode where the hemispherical deposits are seen on the surface. It is shown using mathematical modeling and numerical simulation that this difference cannot be accounted for by simply considering the different distributions of bismuth on the electrode surfaces. Rather, it is concluded that the difference in Voltammetry is mainly due to the morphology/orientation of the deposits formed leading to differences in the kinetics and thermodynamics of the Stripping process.
Eric P Achterberg - One of the best experts on this subject based on the ideXlab platform.
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Cathodic Stripping Voltammetry
Encyclopedia of Analytical Science, 2005Co-Authors: Eric P Achterberg, José L. Barriada, Charlotte B BraungardtAbstract:Cathodic Stripping Voltammetry (CSV) is an analytical technique used for the analysis of low levels of analytes (principally trace metals and sulfur containing organic compounds) in aqueous solutions, and is based on the measurement of a reductive current response as a function of a potential scan towards more negative potentials. The technique is highly sensitive (limits of detection of 10− 10–10− 12 mol l− 1) because of the application of a preconcentrations step prior to the Stripping step. During the preconcentration the analyte is collected on the surface of the working electrode (typically a mercury drop), often in the presence of an added electro-active ligand. The CSV technique has been used for automated measurements of trace metals in marine waters, but a key strength of CSV is in its use in trace metal speciation measurements in natural waters, in particular dissolved iron in marine waters.
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Stripping Voltammetry for the determination of trace metal speciation and in situ measurements of trace metal distributions in marine waters
Analytica Chimica Acta, 1999Co-Authors: Eric P Achterberg, Charlotte B BraungardtAbstract:Progress in marine chemistry has been driven by improved sampling and sample handling techniques, and developments in analytical chemistry. Consequently, during the last 20 years our understanding of marine trace metal biogeochemistry has improved a great deal. Stripping voltammetric techniques (anodic Stripping Voltammetry and adsorptive cathodic Stripping Voltammetry) have made an important contribution to this understanding. The selectivity and extremely low detection limits have made Stripping Voltammetry a widely used technique for trace metal speciation and trace metal distribution measurements in seawater. Stripping Voltammetry is very suitable for ship-board and in-situ applications because of the portability, low cost and capability for automation of the voltammetric instrumentation. Future developments in Stripping Voltammetry can be expected in the field of stand-alone submersible voltammetric analysers, capable of continuous trace metal measurements. Future applications of Stripping Voltammetry can be found in the interactions between trace metal speciation and growth and the functioning of organisms in pristine and metal polluted marine waters.
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Stripping Voltammetry for the determination of trace metal speciation and in-situ measurements of trace metal distributions in marine waters
Analytica Chimica Acta, 1999Co-Authors: Eric P Achterberg, Charlotte B BraungardtAbstract:Progress in marine chemistry has been driven by improved sampling and sample handling techniques, and developments in analytical chemistry. Consequently, during the last 20 years our understanding of marine trace metal biogeochemistry has improved a great deal. Stripping voltammetric techniques (anodic Stripping Voltammetry and adsorptive cathodic Stripping Voltammetry) have made an important contribution to this understanding. The selectivity and extremely low detection limits have made Stripping Voltammetry a widely used technique for trace metal speciation and trace metal distribution measurements in seawater. Stripping Voltammetry is very suitable for ship-board and in-situ applications because of the portability, low cost and capability for automation of the voltammetric instrumentation. Future developments in Stripping Voltammetry can be expected in the field of stand-alone submersible voltammetric analysers, capable of continuous trace metal measurements. Future applications of Stripping Voltammetry can be found in the interactions between trace metal speciation and growth and the functioning of organisms in pristine and metal polluted marine waters. Copyright (C) 1999 Elsevier Science B.V
Rudolf Holze - One of the best experts on this subject based on the ideXlab platform.
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Pencil-Leads as new electrodes for abrasive Stripping Voltammetry
Electroanalysis, 1996Co-Authors: Doris Blum, Wolfgang Leyffer, Rudolf HolzeAbstract:A simplified procedure for abrasive Stripping Voltammetry involving a standard potentiostat, a function generator and common graphitic materials is described.
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Pencil‐Leads as new electrodes for abrasive Stripping Voltammetry
Electroanalysis, 1996Co-Authors: Doris Blum, Wolfgang Leyffer, Rudolf HolzeAbstract:A simplified procedure for abrasive Stripping Voltammetry involving a standard potentiostat, a function generator and common graphitic materials is described.
Doris Blum - One of the best experts on this subject based on the ideXlab platform.
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Pencil-Leads as new electrodes for abrasive Stripping Voltammetry
Electroanalysis, 1996Co-Authors: Doris Blum, Wolfgang Leyffer, Rudolf HolzeAbstract:A simplified procedure for abrasive Stripping Voltammetry involving a standard potentiostat, a function generator and common graphitic materials is described.
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Pencil‐Leads as new electrodes for abrasive Stripping Voltammetry
Electroanalysis, 1996Co-Authors: Doris Blum, Wolfgang Leyffer, Rudolf HolzeAbstract:A simplified procedure for abrasive Stripping Voltammetry involving a standard potentiostat, a function generator and common graphitic materials is described.
