Indirect determination of sulfite using a polyphenol oxidase biosensor based on a glassy carbon electrode modified with multi-walled carbon nanotubes and gold nanoparticles within a poly(allylamine hydrochloride) film

Author(s)

Sartori, Elen Romao ^[1] ; Vicentini, Fernando Campanha ^[1] ; Fatibello-Filho, Orlando ^{[2, 1]}

Affiliation

^[1] Univ Fed Sao Carlos, Dept Quim, BR-13560970 Sao Carlos, SP - Brazil

^[2] Inst Nacl Ciencias & Tecnol Bioanalit, BR-13083970 Campinas, SP - Brazil

• Document type: Journal article
• Source: Talanta; v. 87, p. 235-242, DEC 15 2011.
• Web of Science Citations: 28

Abstract

The modification of a glassy carbon electrode with multi-walled carbon nanotubes and gold nanopartides within a poly(allylamine hydrochloride) film for the development of a biosensor is proposed. This approach provides an efficient method used to immobilize polyphenol oxidase (PPO) obtained from the crude extract of sweet potato (Ipomoea batatas (L.) Lam.). The principle of the analytical method is based on the inhibitory effect of sulfite on the activity of PPO, in the reduction reaction of o-quinone to catechol and/or the reaction of o-quinone with sulfite. Under the optimum experimental conditions using the differential pulse voltammetry technique, the analytical curve obtained was linear in the concentration of sulfite in the range from 0.5 to 22 mu mol L(-1) with a detection limit of 0.4 mu mol L(-1). The biosensor was applied for the determination of sulfite in white and red wine samples with results in close agreement with those results obtained using a reference iodometric method (at a 95% confidence level). (C) 2011 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 09/14454-8 - Modified carbon electrodes with carbon nanotubes and/or metallic nanoparticles in chitosan film for determination of sulphur compounds in petroleum derivatives and food
• Grantee: Elen Julciléia Romão Sartori
• Support Opportunities: Scholarships in Brazil - Post-Doctoral