Selectivity properties of corrin-doped polypyrrole film

We report the synthesis of a new pyrrole-substituted vitamin B-12 derivative functioning as a corrin monomer, its electrochemical copolymerization with pyrrole, and the potentiometric behavior of the resultant electrodes based on the corrin-doped polypyrrole film. Electropolymerization of the corrin monomer on a glassy carbon electrode and its redox properties were evaluated by cyclic voltammetry in acetonitrile in the presence of tetrabutylammonium perchlorate. We investigated the effect of various parameters that control the film properties, such as the concentration of the monomer, potential range, scan rate, and number of scans. The optimal conditions for potentiometric measurements were also determined. We found that the electropolymerized corrin film-based electrode exhibited an anion selectivity pattern that favors thiocyanate and deviates from the Hofmeister series. The obtained electrode demonstrates near-Nernstian behavior for a period of at least 6 months. The detection limit of the electrode along with selectivity coefficients toward various anions was also determined.