Copper

By Burak Derkus and Emel Emregul and Kaan C. Emregul
Published in Talanta NULL 2015

Abstract

In this paper, amperometric enzyme-free sensors using superoxide dismutase (SOD) enzyme as a catalyst for the dismutation reaction of superoxides into oxygen and hydrogen peroxide, enabling superoxide radical detection have been described. For this purpose, the surfaces of screen-printed platinum electrodes have been modified with gelatin composites of CuO, ZnO and CuZn nanoparticles with the expectation of an increase in catalytic effect toward the dismutation reaction. \SOD\ containing electrodes were also prepared for comparative studies in which glutaraldehyde was used as a cross-linker for the immobilization of \SOD\ to the nanocomposite materials. Electrochemical measurements were carried out using a screen-printed electrochemical system that included potassiumferrocyanide (K4[Fe(CN)6]) and potassiumferricyanide (K3[Fe(CN)6]) as the redox probes. The results revealed that the enzyme-free detection method using CuZn nanoparticles can determine superoxide radicals with high performance compared to other detection methods prepared with different nanoparticles by mimicking the active region of superoxide dismutase enzyme. The anodic (ksa) and cathodic (ksc) electron transfer rate constants and the anodic (?a) and cathodic (?c) transfer coefficients were evaluated and found to be ksa=6.31 s?1 and ?a=0.81, ksc=1.48 s?1 and ?c=0.19 for the gelatin

Read Article » Back