title: Superoxide-induced bleaching of streptocyanine dyes: Application to assay the enzymatic activity of superoxide dismutases.
abstract: With the aim of developing a novel superoxide dismutase (SOD) activity assay, a series of polymethinium salts (streptocyanines) were prepared and studied for their ability to be reduced by superoxide radical anion generated either from the pyrogallol autoxidation or by the xanthine oxidase-catalyzed oxidation of xanthine. The nonacarbon chain streptocyanine 9Cl(NEt(2))(2) was found to be relatively stable in neutral buffered aqueous solutions, to be reduced at a significant rate by superoxide, and addition of iron-dependent superoxide dismutase (Fe-SOD) prevented its bleaching, thus constituting a good candidate as a possible superoxide indicator in a spectrophotometric SOD assay. The values found to be optimal for a SOD assay were defined as pH 7.4, wavelength 728nm, xanthine and xanthine oxidase as superoxide source, and a reaction time of 5min. Based on the color change caused by the superoxide-induced bleaching of the streptocyanine, a qualitative colorimetric method for the SOD activity detection is proposed, enabling visual detection within a short time without any instrument.
authors.affiliation: Université Paul Sabatier, Laboratoire de Synthèse et Physicochimie de Molécules d'Intérêt Biologique, UMR 5068, 31062 Toulouse cedex 9, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Vinatier
authors.forename: Valérie
authors.initials: V
authors.lastname: Guieu
authors.forename: Yves
authors.initials: Y
authors.lastname: Madaule
authors.forename: Marie
authors.initials: M
authors.lastname: Maturano
authors.forename: Corinne
authors.initials: C
authors.lastname: Payrastre
authors.forename: Pascal
authors.initials: P
authors.lastname: Hoffmann
mesh_terms: D004396:Coloring Agents / Q000737:chemistry*; D004048:Diethylamines / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry / Q000378:metabolism; D007700:Kinetics; D013482:Superoxide Dismutase / Q000737:chemistry* / Q000378:metabolism; D013481:Superoxides / Q000737:chemistry*; D019820:Xanthine / Q000737:chemistry / Q000378:metabolism; D014969:Xanthine Oxidase / Q000737:chemistry / Q000378:metabolism
chemical_list: D004396:Coloring Agents; D004048:Diethylamines; D013481:Superoxides; D019820:Xanthine; D007501:Iron; D013482:Superoxide Dismutase; D014969:Xanthine Oxidase