Stripping potentiometry

The reader familiar with controlled-potential methodology will have no trouble understanding a controlled-current apparatus. Figure 6.18 illustrates classical approaches to two- and three-electrode constant-current chronopotentiometric experiments (see Chap. 4). The simplicity of these circuits was for many years an attractive feature of chronopotentiometry. Improvements in potentiostats have been largely responsible for a decline in the popularity of chronopot in recent years. Nevertheless, constant-current experiments are even more important with respect to coulometric titrations and stripping potentiometry (Chap. 24). 

J. Wang, X. Cai, C. Jonsson and M. Balakrishnan, Adsorptive stripping potentiometry of DNA at electrochemically pretreated carbon paste electrodes, Electroanalysis, 8 (1996) 20-24. 

Chow, C.W.K., Kolev, S.D., Davey, D.E. and Mulcahy, D.E. (1996) Determination of copper in natural waters by batch and oscillating flow injection stripping potentiometry. Anal. Chim. Acta, 330, 79-87. 

Munoz, E. and S. Palmero. 2005. Analysis and speciation of arsenic by stripping potentiometry A review. Talanta 65 613-620. 

Ultrafiltration was applied to examine the size fractionation of Al, Ca, Cu, Fe, K, Na, and Pb in white and red wines [91]. Metal determinations were performed on the unfiltered wine, the 0.45 p,m membrane-filtered wine and each ultrafiltrate fraction. Aluminum was determined by ET-AAS, while FAAS was employed for Cu and Fe. An electroanalytical technique, stripping potentiometry, was selected for Pb measurement, whereas flame photometry was chosen for K and Na quantification. Fractionation patterns were evaluated and discussed. Castineira et al. [92] combined on-line tangential-flow multistage ultrafiltration with a home-built carbon analyzer and ICP-MS for size fractionation of nonvolatile dissolved organic compounds and metal species in three German white wines. The study showed that the major part of the elements investigated (up to 25) were dissolved in the size fraction of < 1 kDa, with the exception of Ba, Pb, and Sr, which also appeared in other fractions. 

Stripping potentiometry offers several important advantages (over analogous ASV schemes), including reduced susceptibility to organic surfactants and reliable operation in nondeaerated samples. 

Armalis S, Kubiliene E (2000) Stripping potentiometry signal enhancement using mercury film-coated reticulated vitreous carbon working electrode. Anal Chim Acta 423 287—291... 

D. Jagner, L. Renman, and S.H. Stefansdottir. Determination of iron(III) and titanium(IV) as their solochrome violet RS complexes by constant-current stripping potentiometry. Part 1. Automated single-point calibration method for iron(III). Analytica Chimica Acta 281 305-312,1993. J.M. Laporte, J.P. Truchot, F. Ribeyre, and A. Boudou. Combined effects of water pH and salinity on the bioaccumulation of inorganic mercury and methylmercury in the shore crab Carcinus maenas. Marine Pollution Bulletin 34 880-893,1997. 

S.D. Kolev, C.W.K. Chow, D.E. Davey, and D.E. Mulcahy. Oscillating flow injection stripping potentiometry. Analytica Chimica Acta 309 293-302,1995. 

Svancara, I., Ogorevc, B., Novic, M., and Vytfas, K. (2002) Simple and rapid determination of iodide in table salt by stripping potentiometry at a carbon-paste electrode. Anal. Bioanal. Chem., 372 (7-8), 795-800. 

Giacomo, D., PeraLara, L., Daniele, G., Francesco, S., and Turco Vincenzo, L. (2004) Influence of the olive variety and the zone of provenience on selenium content determined by cathodic stripping potentiometry (CSP) in virgin olive oils. Food Chem., 88(1), 135-140. 

Graabaek AM, Jeberg B (1992) Trace element analysis by computerized stripping potentiometry. Intern Labor 22 33-38... 

Natural sweet waters, as samples with apparently the simplest matrix, can be analysed directly by stripping potentiometry, where solely appropriate buffering is needed (see references (37, 38, 48) and references therein). Compared to this, voltammetry usually requires mild digestion, such as UV irradiation however, this operation is not even needed if highly selective pre-cmicentrations are available (e.g. those utilising non-electrolytic principles, open circuit and/or medium exchange see Table 5.1 and reference (21)). 

Gil EP, Ostapczuk P (1993) Nickel and cobalt determination by constant current stripping potentiometry 1. Method development 2. Modifications and check of the method. Eresenius J Anal Chem 346 952-956, 957-960... 

Fig. 6.1 Determination of iodide via its ion pairing and subsequent extraction/re-extraction at the tricresyl-phosphate-based carbon paste electrode (TCP-CPE). (a) Electrode oxidation of the ion pair formed between the protonated TCP and iodide (b) extraction of the released iodine into the carbon paste bulk, a scheme (c) determination of iodide in seawater (synthetic and spiked sample) by stripping potentiometry, dotted line baseline (blank),/m// lines 1) sample-1-0.1 M HNO3 (pH 1) (2, 3) two standard additions as two aliquots, c(I ) = 50 pg Mode constant current...

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