title: Studies on electrochemical properties and scavenge of superoxide anion in aprotic media by using carbon nanotubes powder microelectrode.
abstract: Multiwall carbon nanotubes (MWCNTs) are filled in the cavity at the tip of a microelectrode to form a carbon nanotubes powder microelectrode (CNTs-PME). CNTs-PME was used to study electrochemical properties of superoxide anion in aprotic media. The reversibility of the oxygen/superoxide anion couple (O(2)/O(2)(.-)) at the different powder microelectrode in different aprotic media was compared by cyclic voltammetry (CV). The result indicated that the nearly reversible redox process of the O(2)/O(2)(.-) couple was obtained at a CNTs-PME. The heterogeneous electron transfer rate constant (k(s)) can be measured by steady-state voltammogram and the result is 4.7 x 10(-3) cm s(-1), suggesting that the electrode reaction is a nearly reversible process as expected. The scavenging activities of bilirubin, alpha-tocopherol (vitamin E), are examined, and the experimental results confirm that alpha-tocopherol is the better scavenger toward O(2)(.-) between them.
authors.affiliation: Department of Chemistry, Wuhan University, Wuhan 430072, PR China.
authors.forename: Yingliang
authors.initials: Y
authors.lastname: Wei
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Ji
authors.forename: Xueping
authors.initials: X
authors.lastname: Dang
authors.forename: Shengshui
authors.initials: S
authors.lastname: Hu
mesh_terms: D001663:Bilirubin / Q000737:chemistry / Q000378:metabolism; D004563:Electrochemistry; D004579:Electron Transport; D016166:Free Radical Scavengers / Q000737:chemistry; D008839:Microelectrodes; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D012997:Solvents; D013481:Superoxides / Q000737:chemistry*; D013997:Time Factors; D024502:alpha-Tocopherol / Q000737:chemistry / Q000378:metabolism
chemical_list: D016166:Free Radical Scavengers; D037742:Nanotubes, Carbon; D012997:Solvents; D013481:Superoxides; D024502:alpha-Tocopherol; D001663:Bilirubin; D010100:Oxygen