Voltammetric Behavior Study of Nitrofurazone at Multi-wall Carbon Nanotube-Modified Glassy Carbon Electrode in Aqueous Media

Carbon nanotubes, NTs, have been greatly prominent due to their varied electronic properties, which allow the transduction of signals. The NTs chemical functionalization improves detection traits, eliminating interferences from commercial NTC. Based on the foregoing information, this work aims to evaluate the functionalization influence of carbon nanotubes on glassy carbon electrode by means of electrochemical reduction behavior of nitrofurazone applying cyclic voltammetry. All voltammograms were recorded by using an electrochemical cell with three electrodes: Ag/ACl, Pt and working electrode. Three kinds of working electrodes, functionalized carbon nanotube (GCE-NTC-F), carbon nanotube (GCE-NTC-N) and GCE without modification were evaluated. The chemical functionalization of carbon nanotubes was carried out in a mixture of sulfuric and nitric acids. Solvents such as H2O, EtOH, MeOH, ACN, DMSO, DMF, 1,3-dioxolane were evaluated to get the best NTs dispersing agents. The 1,3-dioxolane solvent was shown to be the best, as it presented greater current signals, despite being nontoxic1. Table I and Figure 1 indicate the results. It can be observed that there are no significant differences among the potential values obtained. The current peak values of both modified electrodes at pH 4.02 are similar and, at pH 7.41, GCE-N presented the highest Ip,c value, indicating that the modification influences positively the electrochemical response of the hydroxylamine derivative formation from the nitrofurazone reduction. Moreover, the functionalization contributes actively to the elimination of the “ghost peaks”, which are irreproducible register by GCE-N.