A ferrocene crown ether–functionalized polypyrrole film electrode for the electrochemical recognition of barium and calcium cations

Transfer of the recognition activity of a ferrocene ionophore to an electrode surface from the homogeneous phase has been successfully accomplished for the first time. The synthesis and electrochemical characterization of a new pyrrole‐substituted ferrocene crown ether are described, followed by the formation of the corresponding polymer film modified electrode. It is shown that the electrode exhibits amperometric recognition in an organic solvent of Ca^2⊕ and Ba^2⊕ among the alkaline and alkaline earth metal cations.