Synthesis and characterization of novel dopamine-derivative: application of modified multi-wall carbon nanotubes paste electrode for electrochemical investigation

Abstract

Novel dopamine-derivative compound, 3,5-diamino-N-(3,4-dihydroxyphenethyl)benzamide (3,5-DAB) was prepared in two steps. In the first step dopamine hydrochloride was reacted with 3,5-dinitrobenzoyl chloride in the presence of propylene oxide. In the second step reduction of nitro groups resulted in preparation of 3,5-DAB in quantitative yield. This material was characterized using conventional spectroscopic methods such as FT-IR and ¹H NMR. In addition, the redox response of a modified carbon nanotubes paste electrode of 3,5-DAB was investigated in aqueous solution at a neutral pH. The result showed that the electrode process has a quasi-reversible response, with ΔE_p, greater than the (59/n) mV expected for a reversible system. Finally, the diffusion coefficient for redox process in paraffin oil matrix obtained using chronoamperometry methods.