Abstract
Abstract A detailed investigation on the electrochemical reduction of copper/amino acid complexes has been carried out using cyclic voltammetry with platinum microdisk electrode in aqueous solution containing 0.1M KCl as the supporting electrolyte. The stage of the first electron attachment is quasi-reversible reaction. The mechanism of the electrode process is following: We investigated the effects of nine different amino acids, that is α-alanine, asparagine, glutamine, glycine, isoleucine, proline, serine, threonine, valine on the rate constant of heterogeneous electron transfer, k0, of the quasi-reversible reaction of Cu(II)L2 calculated by the theory developed by Nicholson.The mean values of k0 with nine different amino acids were between 3.5×10-3 ~ 4×10-4 cm s-1 with a standard deviation of 45%.The order of k0 dose not have simple correlation with that of Cu(I) quantum yield at 313nm. Key words: Copper/amino acid complexes; quasi-reversible reaction; rate constant; heterogeneous electron transfer; quantum yield.