Mg2+-Selective Electrode Comprising Double-Helical DNA as Receptive Entity

Abstract

Abstract Cyclic voltammograms of ferrocyanide/ferricyanide redox couple with a DNA-immobilized electrode gave the peak currents due to the reversible electrode reaction, which were significantly enhanced on adding Mg2+. The electrode responded also to Ca2+ and Ba2+, although the onset concentrations of the electrode response were 50-times larger than that for Mg2+. The selectivity in the order of Mg2+ > Ca2+, Ba2+ >> Na+, K+ seems consistent with the binding affinity of the metal ions with double-helical DNA.