Stripping chronopotentiometry

Electrochemical methods for arsenic determination were initially based on polarography with a dropping mercury electrode. More recent methods, based on anodic stripping voltammetry (ASV), anodic stripping chronopotentiometry (SC), and CSV, rely almost exclusively on the detection of As(III), since As(V) is detected with difficulty because of its perceived electro-inactivity. 

D Stripping chronopotentiometry Potential control Current control E vs. t... 

Kizek, R., Tmkova, T. L., Palecek, E. (2001). Determination of metallothionein at the femtomole level by constant current stripping chronopotentiometry. Anal Chem 73, 4801-4807. 

Tomschik, M., Havran, L., Palecek, E., Heyrovsky, M. (2000). The presodium catalysis of electroreduction of hydrogen ions on mercury electrodes by metallothionein an investigation by constant current derivative stripping chronopotentiometry. Electroanalysis 12, 274-279. 

Riso, R. D. Waeles, M. Pemet-Coudrier, B. Corre, P. Determination of dissolved iron (m) in estuarine and coastal waters by adsorptive stripping chronopotentiometry (SCP). Anal. Bioanal. Chem. 2006, 385, 76-82. 

Normal chronopotentiometry has little importance for analysis. Determinations are possible in the range 10 - 10" mol/L at best. However, the technique is of use in understanding the methods of stripping chronopotentiometry and potentiomet-... 

For the accumulation step, the HMDE and the TMFE are mainly used. The transition times for determinations by stripping chronopotentiometry at these electrodes are approximately ... 

Figure 23 illustrates the form of the curve for the determination of Cd, Tl, and Pb by stripping chronopotentiometry. The normal potential - time curve (A) is compared with the second derivative (B). from which the transition times can be more simply and accurately obtained. A TMFE coated in situ is used for the accumulation. 

For the highest possible sensitivities in stripping chronopotentiometry, and to avoid systematic errors, the sample solutions must not contain oxidizing impurities. Care must therefore be taken to remove the oxygen present in the solution. 

The theory of stripping chronopotentiometry and differential potentiometric stripping analysis has been reviewed [43). 

Potentiometric measurements by ion-selective electrode potentiometry (ISE) or ion-selective field effect transistors (ISFET), stripping voltammetry (SV) and stripping chronopotentiometry (SCP) are analytical techniques capable of giving not only the total concentration of analytes in water samples, but also metal speciation information, since they are sensitive to the free metal fractiOTi. This capability is especially useful for the study of metal distribution and transfer among environmental compartments in water, as previously commented in this subchapter (Fig. 3.1). It s important to stress that SV and SCP are dynamic techniques, whereas ISE and ISFET are equilibrium techniques. For more details on potentiometric measurements, see Chap. 9 vol 2. 

Town RM, van Leeuwen HP (2004) Depletive stripping chronopotentiometry a major step forward in electrochemical stripping techniques for metal ion speciation analysis. Electroanalysis 16 458-471... 

Serrano N, Diaz-Cruz JM, Arino C, Esteban M (2007) Stripping chronopotentiometry in environmental analysis. Electroanalysis 19 2039-2049... 

Kapturski P, Bobrowski A (2007) Silver amalgam film electrode of prolonged application in stripping chronopotentiometry. Electroanalysis 19 1863—1868... 

Eskilsson H, Haraldsson C (1987) Reductive stripping chronopotentiometry for selenium in biological materials in flow system. Anal Chim Acta 198 231-237... 

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