Study of the Molecular Recognition Mechanism of an Ultrathin MIP Film-Based Chiral Electrochemical Sensor

- Atenolol's particular MIP-based chiral recognition mechanism was investigated.
- Chiral recognition requires alternate exposure to aqueous and non-aqueous media.
- Enantiodiscrimination was studied both by a direct and indirect approach.
- Template rebinding significantly changes the permeability of the MIP-layer.
- An additional “gate effect” governs the molecular recognition process.

This study is focused on the molecular recognition mechanism of a methacrylate-based R(+)-atenolol molecularly imprinted polymer (MIP), employed as a chiral sensing interface in the construction of a novel electrochemical sensor. The MIP was electrogenerated as an ultrathin-film onto the surface of a carbon paste working electrode under potentiodynamic conditions in a non-aqueous media. Differential pulse voltammetry served as signal transduction method for the direct and indirect (by means of two redox probes, [Fe(CN)6]3−/4− and 1,1′-ferrocene dimethanol, respectively) detection of the underlying molecular recognition process. The rebinding of the template enantiomer led to changes in solute permeability of the MIP-layer, indicating the presence of a “gate effect” as part of the molecular recognition process.