Preparation of dopamine selective sensors and investigation of some analytical parameters

In this study, various sensors have been developed for rapid, reliable and sensitive determination of dopamine in the presence of ascorbic acid using poly (p-aminobenzene sulfonic acid), poly (m-aminobenzene sulfonic acid) and poly (diphenylamine4-sulfonic acid) modified glassy carbon electrodes. These polymers were prepared by cyclic voltammetry technique in 0.1 M KCl solution. The voltammetric behaviors of dopamine and ascorbic acid on polymeric electrodes prepared at diffirent thicknesses were examined at various supporting electrolyte and pH values. At pH 7.0, while there was no response of negatively charged sulfonic acid polymers to ascorbic acid at 1mM concentration, it caused a higher peak current for dopamine at the same concentration (i.e., 1mM). The results obtained indicated that modified electrodes could also be applied for the determination of dopamine in the presence of ascorbic acid.