Copper–zinc alloy nanoparticle based enzyme-free superoxide radical sensing on a screen-printed electrode
| Autor: | Kaan C. Emregül, Emel Emregul, Burak Derkus |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Inorganic chemistry
Biosensing Techniques 02 engineering and technology 010402 general chemistry Electrochemistry 01 natural sciences Redox Catalysis Analytical Chemistry Superoxide dismutase chemistry.chemical_compound Superoxides Alloys Ferricyanides Hydrogen peroxide Electrodes biology Superoxide Dismutase Superoxide Electrochemical Techniques 021001 nanoscience & nanotechnology Amperometry 0104 chemical sciences Kinetics Zinc chemistry Electrode biology.protein Nanoparticles Printing Zinc Oxide 0210 nano-technology Oxidation-Reduction Copper Ferrocyanides |
| Zdroj: | Talanta. 134:206-214 |
| ISSN: | 0039-9140 |
| DOI: | 10.1016/j.talanta.2014.11.003 |
| Popis: | 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 crosslinker for the immobilization of SOD to the nanocomposite materials. Electrochemical measurements were carried out using a screen-printed electrochemical system that included potassiumferrocyanide (K-4[Fe(CN)(6)]) and potassiumferricyanide (K-3[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 (ks(a)) and cathodic (ks(c)) electron transfer rate constants and the anodic (alpha(a)) and cathodic (alpha(c)) transfer coefficients were evaluated and found to be ks(a)=6.31 s(-1) and alpha(a)=0.81, ks(c)=1.48 s(-1) and alpha(c)=0.19 for the gelatin-CuZn-SOD electrode; ks(a)=6.15 s(-1) and alpha(a)=0.79, ks(c)=1,63 s(-1) and alpha(c)=0.21 for the enzyme-free gelatin-CuZn electrode. The enzyme-free electrode showed nearly 80% amperometric performance with respect to the enzyme containing electrode indicating the superior functionality of enzyme-free electrode for the detection of superoxide radicals. (C) 2014 Elsevier B.V. All rights reserved. |
| Databáze: | OpenAIRE |
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