Two beta -cyclodextrin (beta -CyD) derivatives, having both ferrocene and e
thylmethylsulfide moieties, were synthesized. They spontaneously adsorbed o
nto a gold surface, which was characterized by linear relationship between
the anodic peak current and potential sweep rate in the cyclic voltammogram
s obtained with the modified gold electrodes. The anodic and cathodic peak
positions of the surface-confined ferrocene species were not identical, whi
ch indicates that the electrode reactions of the ferrocene species were dep
ressed, probably due to the intramolecular complexation with their CyD cavi
ties. Cyclic voltammometric studies with soluble electroactive probes (Fe(C
N6)(3-) and ferrocenecarboxylic acid) revealed that the two beta -CyD deriv
atives formed CyD monolayers with different permeability to each other. (C)
2001 Elsevier Science B.V. All rights reserved.