title: 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).
authors.forename: Almaz S
authors.initials: AS
authors.lastname: Jalilov
authors.forename: Chenhao
authors.initials: C
authors.lastname: Zhang
authors.forename: Errol L G
authors.initials: EL
authors.lastname: Samuel
authors.forename: William K A
authors.initials: WK
authors.lastname: Sikkema
authors.affiliation: Hematology, Department of Internal Medicine, University of Texas Houston Medical School , Houston, Texas 77030, United States.
authors.forename: Gang
authors.initials: G
authors.lastname: Wu
authors.affiliation: Hematology, Department of Internal Medicine, University of Texas Houston Medical School , Houston, Texas 77030, United States.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Berka
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Kent
authors.affiliation: Hematology, Department of Internal Medicine, University of Texas Houston Medical School , Houston, Texas 77030, United States.
authors.forename: Ah-Lim
authors.initials: AL
authors.lastname: Tsai
authors.forename: James M
authors.initials: JM
authors.lastname: Tour
keywords: antioxidant; carbon nanoparticles; oxidation; oxygen reduction; superoxide