| Abstract
| - A chiral sensing electrode has been prepared by coating an indium tin oxide (ITO) substrate with a hybridfilm of metal complexes and a clay layer (montmorillonite). By applying the combined method of theLangmuir−Blodgett and self-assembly techniques, a monolayer of a water-soluble chiral metal complex (Λ-[Os(phen)3]2+), which acted as a mediator of oxidizing a target molecule, was fixed electrostatically onto asingle-layered clay film. Chiral sensing was demonstrated by monitoring a photocurrent when the electrodewas in contact with an aqueous NaClO4 solution of 1,1‘-2-binaphthol. As a result, the S-1,1‘-2-binaphtholgave a photocurrent 1.8 times higher than the R-isomer at the applied potential of 700 mV (vs Ag|AgCl|KCl(sat)). Detection limit was determined to be 40 μM from the concentration dependence of a response current.Mechanisms for chiral sensing effect were explained in terms of the stereoselective binding of 1,1‘-2-binaphtholwith adsorbed Λ-[Os(phen)3]2+ on a clay surface.
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