The adamantyl moieties of adamantylnaphthalene diimide (AND) can be incorporated into the cavity of ferrocenyl-beta-cyclodextrin even where they are bound to double stranded DNA by threading intercalation. When this ternary complex is formed on the DNA probe-immobilized electrode, electrochemical DNA detection is feasible: the electrode hybridized with target DNA gave rise to a current peak corresponding to the ferrocene oxidation upon treatment with AND and ferrocenyl-beta-cyclodextrin (Fc-beta-CD).