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Mechanistic Study of the Conversion of Superoxide to Oxygen and Hydrogen Peroxide in Carbon Nanoparticles.

ABSTRACT: Hydrophilic carbon clusters (HCCs) are oxidized carbon nanoparticles with a high affinity for electrons. The electron accepting strength of HCCs, employing the efficient conversion of superoxide (O2(•-)) to molecular oxygen (O2) via single-electron oxidation, was monitored using cyclic voltammetry and electron paramagnetic resonance spectroscopy. We found that HCCs possess O2 reduction reaction (ORR) capabilities through a two-electron process with the formation of H2O2. By comparing results from aprotic solvents to those obtained from ORR activity in aqueous media, we propose a mechanism for the origin of the antioxidant and superoxide dismutase mimetic properties of poly(ethylene glycolated) hydrophilic carbon clusters (PEG-HCCs).

SUBMITTER: Jalilov AS

PROVIDER: S-EPMC4920082 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Mechanistic Study of the Conversion of Superoxide to Oxygen and Hydrogen Peroxide in Carbon Nanoparticles.

Jalilov Almaz S AS Zhang Chenhao C Samuel Errol L G EL Sikkema William K A WK Wu Gang G Berka Vladimir V Kent Thomas A TA Tsai Ah-Lim AL Tour James M JM

ACS applied materials & interfaces 20160610 24

Hydrophilic carbon clusters (HCCs) are oxidized carbon nanoparticles with a high affinity for electrons. The electron accepting strength of HCCs, employing the efficient conversion of superoxide (O2(•-)) to molecular oxygen (O2) via single-electron oxidation, was monitored using cyclic voltammetry and electron paramagnetic resonance spectroscopy. We found that HCCs possess O2 reduction reaction (ORR) capabilities through a two-electron process with the formation of H2O2. By comparing results fro ...[more]

PMID: 27245481

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