title: Catalytic activity of thiacalix[4]arenetetrasulfonate metal complexes on modified anion-exchangers for ascorbic acid oxidation.
abstract: The catalysis of ascorbic acid (AsA) oxidation by anion-exchangers modified with metal complexes of thiacalix[4]arenetetrasulfonate (Me-TCAS[4]A-500, Me=Mn(3+), Fe(3+), Co(3+), Ce(4+), Cu(2+), Zn(2+), Ni(2+), and H2) were investigated. Me-TCAS[4]A-500 (Me=Mn(3+), Fe(3+), Ce(4+), and Cu(2+)) all exhibited the ability to catalyze the oxidative reaction of AsA to dehydroascorbic acid. However, in the presence of high concentrations of AsA, only Cu(2+)-TCAS[4]A-500 was capable of complete oxidation of the acid. Moreover, after six repeat uses, Cu(2+)-TCAS[4]A-500 maintained high and relatively constant catalytic activity. Prior treatment of glucose solutions with Cu(2+)-TCAS[4]A-500, even in the presence of high AsA concentrations, enabled the satisfactory determination of glucose without interference by AsA. Cu(2+)-TCAS[4]A-500 will therefore be applicable as an artificial substitute for ascorbate oxidase, and may be useful as a means to eliminate AsA interference during the analysis of vital compounds such as glucose and uric acid.
authors.affiliation: Department of Biochemistry, Faculty of Science, Okayama University of Science.
authors.forename: Junichi
authors.initials: J
authors.lastname: Odo
authors.forename: Tomomi
authors.initials: T
authors.lastname: Hirashima
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hayashida
authors.forename: Asuka
authors.initials: A
authors.lastname: Miyauchi
authors.forename: Mami
authors.initials: M
authors.lastname: Minemoto
authors.forename: Masato
authors.initials: M
authors.lastname: Iuchi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Inoguchi
mesh_terms: D000838:Anions / Q000737:chemistry; D001205:Ascorbic Acid / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000737:chemistry*; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry*
chemical_list: D000838:Anions; D056831:Coordination Complexes; D010636:Phenols; C446239:thiacalix(4)arenetetrasulfonate; D001205:Ascorbic Acid