Electroenzymatic oxidation of polyaromatic hydrocarbons using chemical redox mediators in organic media

• Published in: Electrochemistry communications Vol. 10; no. 1; pp. 108 - 112
• Main Authors: Hernandez, Camilo E. La Rotta, Werberich, Diogo S., D’Elia, Eliane
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 2008; Amsterdam Elsevier Science; New York, NY
• Subjects: Biological and medical sciences; Chemistry; Electrochemistry; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General and physical chemistry; Horseradish peroxidase; Kinetics and mechanism of reactions; Mediators; Molecular biophysics; Photoactive quinones; Physical chemistry in biology; Polyaromatic hydrocarbons; Horseradish peroxidase; Photoactive quinones; Mediators; Polyaromatic hydrocarbons; Hydrocarbon; Enzyme; Quinone; Transition metal; Polycyclic aromatic compound; Electrodes; Organic solvent; Peroxidases; Mediator; Oxidation; Peroxidase; Oxidoreductases; Copper; Electrochemical reaction
• ISSN: 1388-2481; 1873-1902
• DOI: 10.1016/j.elecom.2007.10.028

The bioelectrochemical oxidation of two polyaromatic hydrocarbons (PAH): anthracene (ANT) and pyrene (PYR), using horseradish peroxidase (HRP) resulting in the synthesis of photoactive polyaromatic quinones in organic media was studied. The electrochemical generation of hydrogen peroxide was compared with its direct addition in concentrations of up to 0.0012 mol L −1. In addition, three different chemical redox mediators were evaluated: ABTS, thionin and ortho-aminophenol. In a reaction medium containing 30% acetone and ABTS as mediator with a molar ratio mediator/PAH of 1:10, HRP attained the highest level of oxidation of PAH (1 × 10 −3 mol L −1): ANT (94%) and PYR (91%), producing 9,10-anthraquinone and mainly 1,2 and 4,5-pyrenequinones, respectively.