Resumo

GIL, E. S.; MULLER, L.; SANTIAGO, M. F.  e  GARCIA, T. A.. Biosensor Based on Brut Extract from Laccase (Pycnoporus sanguineus) for Environmental Analysis of Phenolic Compounds. Port. Electrochim. Acta [online]. 2009, vol.27, n.3, pp.215-225. ISSN 0872-1904.

Laccase is a poliphenoloxidase enzyme that catalyzes the oxidation of catechol compounds in the corresponding quinones. The current obtained in this redox process can be used for quantitative analysis. In this work, a carbon paste biosensor modified with a crude enzymatic extract of the Py cnoporus sanguineus fungi as a lacase source is proposed for catechol determination and other phenolic compounds. The effect of carbon paste and electrolyte composition, pH from 3.0 to 8.0, scan rate from 10 to 40 mVs^-1 and potential pulse amplitude from 10 to 60 mV on the differential pulse voltammetric response was investigated. The analytical curves were linear in the catechol concentration range from 2.0 x 10^-5 to 7.0 x 10^-4 molL^-1, with detection limits of 4,5 x 10^-6 molL ^-1. This biosensor was used for the determination of different kind of phenolic compounds, presenting better response for catechol, hydroquinone and resorcine.

Palavras-chave : biosensor; laccase; phenolic compounds; crude enzymatic extract; catechol.

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