Electrochemical Study of the Complex [Cu(pdto)(H2O)]2+ (pdto=1,8-bis(2-pyridyl)-3,6-dithiaoctane) in the Presence of the Superoxide. Toward an Electrochemical Method to Measure SOD Activity

This work presents the electrochemical characterization of Cu(NO3)(2)center dot 2.5H(2)O, [Cu(pdto) H2O](PF6)(2) and superoxide ion in DMSO. The electrochemical processes Cu(II) + 2e -> Cu(0), [Cu(pdto)(H2O)](2+) + 1e ->[Cu(pdto)](+), [Cu(pdto)](+) + 1e -> Cu(0), O-2(center dot-)-> O-2 + 1e(-), and O-2(center dot-) + 1e + H+-> OOH- were identified. The electrochemical response of a mixture of the complex [Cu(pdto)(H2O)](2+) with superoxide was studied and, according to this result, it was possible to establish a simple methodology that indicates if a compound presents a superoxide dismutase (SOD)-like mechanism.