Self-assembled monolayers - a way to personalize the electrode surface

We recently investigated the electrochemical reactivity of a thione-derivative of canthaxanthin (a natural carotenoid) in the form of a SAM on the gold electrode surface. The electrochemical studies evidenced the carotenoid chemisorption on the electrode surface. As a result, the blocking behavior of the modified electrode towards the electron-transfer reactions of some redox probe, as [Fe(CN)6]3- or a ferrocene derivative, was evidenced. Another direction to personalize the electrode surface is by chemisorption of organic compounds with binding sites, in order to achieve a more specific response of the electrode. We in estigated the electron transfer reaction of copper(II) ion as a surface-immobilized complex compound, using modifiers with [O,N] binding sites and a sulfur atom as the bridge towards the electrode surface. The electrochemical response of the Cu(II)/Cu I) redox couple should provide useful information about the integrity of the organized monolayer. Also, on the basis of a preconcentration/stripping procedure, very low concentration of copper ion in the solution should be detected.