With regards to HNO3, HClO4and H2SO4, the peak current of TBwas appeared to be comparable mutually, however, with slightly highermagnitude and lower background current noticed for H2SO4.Nevertheless, the most propitious voltammetric profile of 1 mM TB withthe highest current response and the lowest background current wasregistered in the presence of 0.1 M H2SO4. In addition, it is obviousfromFig. 1that the use of HCl was not convenient owing to weakerelectrochemical activity of TB resulting to its lower current responseand very high background current. Overall, taking all aspects regardingthe effect of supporting electrolyte into account and bearing in mind thewell-defined oxidation peak of TB compared to other acids, 0.1 MH2SO4was chosen as suitable supporting electrolyte for subsequent voltammetric measurements.