Copper Nanoparticles for Ascorbic Acid Sensing in Water on Carbon Screen-printed Electrodes.

A carbon screen-printed electrode was modified with copper nanoparticles from their dispersion obtained via pulsed laser ablation of a copper target in ethanol. The modified electrode exhibited activity in ascorbic acid electrochemical oxidation, giving an anodic current peak on voltammograms. Linear sweep and cyclic voltammetry have shown a linear dependence of the signal (both peak height and peak area) on the ascorbic acid concentration. The linear range from 1 to 250 μM of ascorbic acid was studied, and the detection limit was experimentally found to be 0.5 μM. The amperometric response to the addition of ascorbic acid portions into the solution was recorded. For the case of the simultaneous presence of ascorbic acid and glucose, two separate signal were obtained. Thus, the modified electrodes are characterized by the following advantages: disposable use; small amount of the samples required for the analysis; lower price (cheap copper is used); simple and easy modification procedure; good metrological characteristics; selectivity.