Magnetic silver(I) ion-imprinted polymeric nanoparticles on a carbon paste electrode for voltammetric determination of silver(I)

Magnetic silver ion imprinted polymer nanoparticles (mag-IIP-NPs) were prepared and used as a recognition element in electrochemical detection of silver(I). The procedure involves two steps: (a) the extraction of the Ag(I) by the mag-IIP-NPs, and (b) determination of the preconcentrated Ag(I) ions on the surface of the magneto carbon paste electrode (MCPE) using differential pulse voltammetry. The amount of sorbent, pH value of the sample solution, extraction time, supporting electrolyte, reduction potential and reduction time were optimized. Under optimal conditions and at a working voltage of +0.02 V (vs. Ag/AgCl), the method displays a linear response in the 0.05 to 150 μg⋅L−1 Ag(I) concentration range. Other features include a low detection limit (15 ng⋅L−1), a remarkable selectivity and good reproducibility (with an RSD of 4.7%). The results obtained with this analytical assay when analyzing different water samples were compared with the data obtained by GF-AAS, and the results agreed satisfactorily. In our perception, this approach also may be extended to electrochemical detection for other ions, and this makes it a widely applicable strategy for heavy metal ion analysis.