Potentiometric Shipping Analysis

Other versions of shipping analysis, including potentiometric stripping, adsorptive shipping, and cathodic stripping schemes, have been developed to further expand its scope and power. 

Potentiometric stripping analysis (PSA), known also as stripping potenhometry, differs from ASV in the method used for stripping the amalgamated metals (22). hi this case, the potentiostatic control is disconnected following the preconcentration, and the concentrated metals are reoxidized by an oxidizing agent [such as O2 or Hg(II)] that is present in the solution  

FIGURE 3-15 Stripping potentiograms for a solution containing 100 pg L-1 tin, cadmium, and lead 80 s accumulation at — 1.40 V Original (a) and differential (b) displays. (Reproduced with permission from reference 22.). 

About 20 amalgam-forming metals, including Pb, Sn, Cu, Zn, Cd, Bi, Sb, Tl, Ga, In and Mn, are easily measurable by stripping strategies (ASV and PSA) based on cathodic deposition onto mercury electrodes. Additional metals, such as Se, Hg, Ag, Te and As are measurable at bare solid electrodes such as carbon or gold. 

Adsorptive stripping analysis greatly enliances the scope of stripping measurements toward numerous trace elements (23,24). This relatively new strategy involves the 

Besides trace metals, adsorptive stripping voltammetry has been shown to be highly suitable for measrrring organic compormds (including cardiac or anticancer drugs, nucleic acids, vitamins, and pesticides) that exhibit srrrface-active properties. 

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