A non-enzymatic ethanol sensor based on a nanostructured catalytic disposable electrode†
Herein, a simple and fast method for the electrocatalytic detection of ethanol using disposable nanostructured screen-printed carbon electrodes (SPCEs) is presented for the first time. Platinum nanoparticles (PtNPs), prepared in the presence of citrate and later purified and dispersed in ultrapure water, were employed in the modification of the SPCEs (SPCE-PtNPs). The synthetized nanoparticles and the catalytic nanostructured solid surface were characterized with transmission electron microscopy (TEM) and with scanning electron microscopy (SEM), respectively. Both systems were also characterized using voltammetric techniques. Finally, the PtNPs modified SPCEs were employed for the electro-oxidation of ethanol in an alkaline medium using portable instrumentation. The electrochemical results revealed that PtNPs can effectively enhance the electron transfer between the analyte of interest and the electrode. The content of ethanol was assayed in real samples (alcoholic beverages) revealing an accurate performance. Additionally, a stability study of the nanostructured surface was carried out. The results obtained corroborate the promising catalytic activity of PtNPs in ethanol detection using disposable, cost-effective and miniaturized sensing devices.