Fe(III)-DOTA/Fe(III)-NOTA Complexes: Attractive Alternative Markers for Future Electrochemical Biosensors

Metallic complexes of macrocycles chelators 1,4,7-triazacyclononane-N,N,N-triacetic acid (NOTA) and 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) were synthetized with iron (III) giving Fe(III)-DOTA and Fe(III)-NOTA complexes. They were studied in comparison of ferricyanide and ferrocenemethanol on cyclic voltammetry with glassy carbon working electrode (GC) and screen-printed carbon electrode (SPCE). Diffusion coefficients and heterogeneous electron transfer rate constants were determined with Randles-Sevcik and Nicholson-Lavagnini methods. Using SPCE. The average values of diffusion coefficient and transfer rate constant were respectively of 1.34 x 10(-6)cm(2)s(-1)and 1.01 x 10(-3)cm s(-1)for Fe(III)-DOTA, and 4.32 x 10(-6)cm(2)s(-1)and 1.14 x 10(-3)cm s(-1)for Fe(III)-NOTA. Interestingly, characteristics of the synthetized complexes on SPCE compete advantageously with those of ferricyanide and ferrocenemethanol, making Fe(III)-DOTA and Fe(III)-NOTA potential markers for future biosensors development.