Persistence of dopamine and small oxidation products thereof in oxygenated dopamine solutions and in “polydopamine” films

This communication reports additional experimental evidence, on the basis of UV–vis spectroscopy and cyclic voltammetry (CV), that oxygenated dopamine solutions still contain dopamine or related molecules even after one week of oxidation. Similarly, the “polydopamine” films deposited on amorphous carbon electrodes, display CV curves consistent with the presence of dopamine and related small molecules. As a consequence and a new result, dopamine solutions oxygenated during one week can still be used to deposit “polydopamine” films on amorphous carbon electrodes by means of CV as well as by direct deposition from solution.