title: Modeling the surface phenomena in carbon paste electrodes by low frequency impedance and double-layer capacitance measurements.
abstract: Impedance and capacitance studies have been performed with covalently coupled Glucose oxidase (GOD) enzyme, covalently coupled flavin adenine dinucleotide (FAD), reconstituted GOD enzyme and blank carbon paste electrodes to study the changes in the electrochemical interfacial properties. Impedance studies were performed using a low frequency impedance technique and the electrochemical surface capacitance was measured by a pulse technique. We have attempted to fit the experimental values to an equivalent circuit model. The Randles' cell circuit with Warburg impedance modeled well the experimental values and the behavior of the enzyme electrodes. The individual components of the model were calculated and the parameters were explained. The blank paste electrode showed a constant phase element behavior.
authors.affiliation: Department of Biochemistry, School of Life Sciences, University of Hyderabad, India.
authors.forename: D
authors.initials: D
authors.lastname: Savitri
authors.forename: C K
authors.initials: CK
authors.lastname: Mitra
mesh_terms: D002244:Carbon / Q000737:chemistry*; D004553:Electric Conductivity; D017097:Electric Impedance; D004566:Electrodes; D004800:Enzymes, Immobilized; D005182:Flavin-Adenine Dinucleotide / Q000737:chemistry; D005949:Glucose Oxidase / Q000737:chemistry; D008962:Models, Theoretical
chemical_list: D004800:Enzymes, Immobilized; D005182:Flavin-Adenine Dinucleotide; D002244:Carbon; D005949:Glucose Oxidase