Molecular anchors—mimicking metabolic processes in thiol analysis

Abstract

The interaction between various novel naphthoquinones and glutathione was explored using a variety of electrochemical techniques. An adamantane derivatised quinone was found to adsorb strongly to carbon surfaces providing a robust film possessing a distinct and consistent voltammetric profile which is markedly different from solution based species. The anodic peak process was found to respond to increasing additions of glutathione and the analytical merits have been assessed. In contrast to conventional thiol–quinone electrochemistry, the detection pathway involves the solubilisation and removal of the hydrophobic quinone derivative through conjugation with glutathione. The peak potential (+0.2 V vs. Ag/AgCl) is such that an unambiguous response to glutathione can be achieved in the presence of a significant excess (1 mM) of common physiological components.