Abstract

SANCHEZ-ALVAREZ, Annelis O.; MELENDEZ, J. Andres; SILVESTRY-RAMOS, Mariena  and  CABRERA, Carlos R.. Copper-Zinc Superoxide Dismutase (CuZn-SOD) Electrochemical Catalytic Amplification Sensing at Pt Ultramicroelectrodes. J. Mex. Chem. Soc [online]. 2023, vol.67, n.4, pp.505-517.  Epub Apr 26, 2024. ISSN 1870-249X.  https://doi.org/10.29356/jmcs.v67i4.1963.

Copper/zinc superoxide dismutase (CuZnSOD), a 32.5 kDa metalloprotein with a radius of ca. 2.1 nm, catalyses the superoxide to hydrogen peroxide and molecular oxygen. At the femtomolar concentration range, has been sensed through electrochemical catalytic amplification using a Pt ultramicroelectrode. During amperometric (i vs. t) analysis, cathodic and anodic current transitions peaks were seen, in agreement with the metalloprotein catalytic mechanism. The current amplitudes were analyzed and correspond to the CuZnSOD dimensions. Thermal treatment of metalloprotein samples at 80 °C showed larger current spikes suggesting aggregation without losing its catalytic capability. The size was confirmed by transmission electron microscopy.

Keywords : Electrochemical catalytic amplification; copper zinc superoxide dismutase (CuZnSOD); metalloproteins; Pt ultramicroelectrodes.