Interfacial Molecular Recognition. Binding of Ferrocenecarboxylate to β-Aminocyclodextrin Hosts Electrostatically Immobilized on a Thioctic Acid Monolayer

The interfacial binding properties of electrodes prepared by the electrostatic immobilization of an adlayer of positively charged β-aminocyclodextrin (β-ACD) hosts on a self-assembled monolayer of thioctic acid on gold were investigated using Osteryoung square wave voltammetry. The results indicate that the water-soluble ferrocenecarboxylate (Fc-COO - ) guest was effectively bound by the interfacial β-ACD hosts, with binding constants in the range (2−5) × 10 4 M -1 . The measured binding constants were found to increase slightly with the surface density of immobilized hosts.