Study on Redox Behaviour of Dopamine and its Complexes with Cu (II) and Mg (II) ions

Abstract

The complexations of dopamine with Cu (II) and Mg (II) ions and their redox behaviour have been studied in aqueous solution using electrochemical methods such as, cyclic voltammetry (CV) and chrono coulometry (CC). The redox behaviour of Cu (II) and Mg (II) ions in absence and in presence of dopamine has been investigated. Dopamine hydrochloride (DPH) shows a two-electron transfer quasi-reversible charge transfer reaction on platinum electrode and similar redox behaviour was observed in case of Mg (II). A two-step redox process is observed for Cu (II) in aqueous solution. The values of charge transfer rate constants for the ligand DPH and for pure metals Cu (II) and Mg (II) are higher than those of Cu (II)DPH and Mg (II)-DPH system indicating considerable complexation. CC data was analyzed to evaluate the extent of adsorption of the reactants or products on the surface. Key words: Complexation, Adsorption, Redox behaviour, Charge transfer Dhaka Univ. J. Pharm. Sci. Vol.4(2) 2005 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website