A STUDY OF SELECTIVE PERMEABILITY OF BETA -CYCLODEXTRIN DERIVATIVES SELF-ASSEMBLED MONOLAYERS ON GOLD

The ordered self-assembled monolayers of beta-cyclodextrin derivatives on gold have been prepared with two kinds of lipoyl-beta-cyclodextrin derivatives which are more flexible than heptakis(dodecyl sulfide) be ta-cyclodextrin. The evidence of selective permeability for the organi c species which can form host-guest inclusion complexes with beta-cycl odextrin was obtained by cyclic votammetry for electroactive species o f [Fe(CN)(6)](3-)/[Fe(CN)(4)](4-) and ferrocence carboxylic acid(FCA) on the self-assembled monolayers electrode, FCA can permeat through th e beta-cyclodextrin monolayers by complexing with beta-cyclodextrin. H owever, the electrode reaction for [Fe(CN)(6)](3-)/[Fe(CN)(4)](4-) is efficiently inhibited by the beta-cyclodextrin cavity. On the other ha nd, the permeability for FCA was shown to be able to be inhibited by a dding other organic guests such as borneol and ursodeoxycholic acid. T he promising applications of the selective permeability of beta-cyclod extrin self-assembled monolayers are for selective membrane transport and selective electrochemical analysis.