High performance electrochemical sensors for dopamine and epinephrine using nanocrystalline carbon quantum dots obtained under controlled chronoamperometric conditions

This work describes a chronoamperometrically-controlled synthesis of nanocrystalline carbon quantum dots (C-dots) and their study based on UV-Vis, Raman, FTIR, fluorescence spectroscopy, atomic force and high resolution transmission electron microscopy. The electrochemical synthesis was carried out using 1-propanol as a carbon source and the C-dots properties exhibited a great dependence on the electrolysis time spent in the process. The C-dots were applied as prepared, on the surface of a glassy carbon electrode, showing excellent electrochemical response in the simultaneous determination of dopamine and epinephrine. The detection limits for the two analytes were 4.6 nmol L-1 and 6.1 nmol L-1, respectively, and the overall electrode performance exhibited a much better electrocatalytic response, in relation to the similar carbon modified electrodes prepared under comparable conditions, with single wall carbon nanotubes and graphene oxide. (C) 2016 Elsevier Ltd. All rights reserved.