Eu(III) indirect probe to investigate interaction of DOPA (3,4,di-hydroxyphenylalanine) and dopamine (3,4-dihydroxy phenyl ethyl amine) using electrochemical methods

Eu(III) can be utilized as an indirect electrochemical probe to investigate the interaction of bio-molecules such as DOPA and Dopamine with Ca(II) in vitro. The interaction of DOPA and Dopamine with Eu(III)-Eu(II) redox pair was investigated by electrochemical techniques. Both the neurotransmitters are structurally related and undergo interaction with Eu(III). Eu(III) coordinates with DOPA and Dopamine through five-member chelate rings via carboxylic oxygen and amino nitrogen. The electrode kinetic parameters viz, transfer coefficient (alpha(na)), diffusion coefficient (D), forward heterogeneous rate constant (k(fh)(0)) were evaluated for Eu(III)-DOPA/Eu(III)-Dopamine. The results obtained were used to investigate the nature of interaction of Eu( with multi-donor biomolecules. The possible mechanism was also proposed.