Stripping chronopotentiometry at scanned deposition potential (SSCP): An effective methodology for dynamic speciation analysis of nanoparticulate metal complexes

The features of stripping chronopotentiometry at scanned deposition potential (SSCP) are reviewed and placed in context with voltammetric and other dynamic speciation techniques. The advantages of SSCP for speciation analysis of nanoparticulate metal complexes are highlighted. Analogous to other electrochemical techniques, the SSCP wave is rich in information: the measurements from the foot to the plateau of the wave access the relevant parts of the stability distribution and the rate constant distributions. The complete depletion regime of SSCP offers particular advantages due to its ability to unambiguously distinguish between various factors that can confound interpretation of data from other electroanalytical methods, including electrochemical irreversibility, kinetically controlled currents, reduced diffusion coefficient of the metal complex species as compared to the free metal ion, and chemical heterogeneity in the intrinsic binding affinity.