Epinephrine Oxidation in the Presence of Interfering Molecules on Gold and Gold Electrodes modified with Gold Nanoparticles and Thiodipropionic Acid in Aqueous Solution. A Comparative Study

Thiodipropionoc acid (TDPA), cysteamine (CA) and gold nanoparticles (Au-NPs) modified gold pure electrodes have been applied in voltammetric sensors for simultaneous detection of epinephrine (EP), ascorbic (AA) and uric (UA) acids. Modified electrodes with self assembled layers (SAMs) show high selectivity, sensitivity, reproducibility and stability. A linear relationship between the epinephrine concentration and the current response is obtained in the range of 0.1 mu M to 0.65 mu M with the detection limit <= 0.065 mu M for the electrodes modified at 2D surface and in the range of 0.1 mu M to 0.75 mu M with the detection limit <= 0.082 mu M for the electrodes modified at the 3D surface.