title: Electrocatalytic activity of cobalt phthalocyanine CoPc adsorbed on a graphite electrode for the oxidation of reduced L-glutathione (GSH) and the reduction of its disulfide (GSSG) at physiological pH.
abstract: Modified electrodes coated by adsorbed cobalt phthalocyanines are known to show substantial electrocatalytic activity for the electro-oxidation of several thiols in alkaline aqueous solution. In this context, we explore in this study the electrocatalytic activity of adsorbed cobalt phthalocyanine (CoPc) on ordinary pyrolytic graphite electrode for the oxidation of reduced L-glutathione GSH and the reduction of its disulfide GSSG at physiological pH. To do so, cyclic and rotating disk voltammetries were performed and the amperometric results show that a stable electrochemical sensing material, with good reproducibility and sensitivity (in accordance with the concentrations of GSH expected in biological media), can be easily achieved. This opens the way for the design of an electrochemical sensor able to detect these two analytes in biologically relevant experimental conditions (in terms of pH).
authors.affiliation: Laboratoire de Pharmacologie Chimique et Génétique, UMR CNRS 8151/U INSERM 640, Ecole Nationale Supérieure de Chimie de Paris, 11, rue Pierre et Marie Curie, 75231 Paris Cedex 05, France.
authors.forename: Nazaré
authors.initials: N
authors.lastname: Pereira-Rodrigues
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Cofré
authors.forename: José H
authors.initials: JH
authors.lastname: Zagal
authors.forename: Fethi
authors.initials: F
authors.lastname: Bedioui
mesh_terms: D002384:Catalysis; D004220:Disulfides / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D005978:Glutathione / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007211:Indoles / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D004220:Disulfides; D007211:Indoles; D009942:Organometallic Compounds; C063633:cobalt phthalocyanine; D006108:Graphite; D005978:Glutathione