Preparation and Electrochemical Characterization of a β-Cyclodextrin-Based Chemically Modified Electrode

Abstract

The preparation and the voltammetric characterization of a chemically modified electrode (CME) based on a suitable thiolate β-cyclodextrin (βCD) derivative in the form of self-assembled monolayer (SAM) is described. The quality of SAM was studied by double layer capacitance measurements, reductive desorption and cyclic voltammetry. Species unable (hexacyanoferrate) or able (ferrocenecarboxylic acid and hydroquinone) to permeate the βCD cavity were used to test the CME by cyclic voltammetry. The CME can work as channel sensor so it can be used for the detection of nonelectroactive analytes forming a strong inclusion complex with βCD if a suitable marker able to permeate the βCD cavity is used. This approach was also used for the evaluation of the conditional constants of the surface host-guest complexes formed by βCD with analytes in test (trimethyilcetylammonium ion and ursodeoxycholic acid).