Determination of phenolic acids using Trametes versicolor laccase.

Ege University, Faculty of Science, Biochemistry Department, 35100 Bornova-Izmir, Turkey.
Talanta (Impact Factor: 3.5). 03/2007; 71(1):312-7. DOI: 10.1016/j.talanta.2006.04.032
Source: PubMed

ABSTRACT Two biosensors based on Trametes versicolor laccase (TvL) were developed for the determination of phenolic compounds. Commercial oxygen electrode and ferrocene-modified screen-printed graphite electrodes were used for preparation of laccase biosensors. The systems were calibrated for three phenolic acids. Linearity was obtained in the concentration range 0.1-1.0muM caffeic acid, 0.05-0.2muM ferulic acid, 2.0-14.0muM syringic acid for laccase immobilised on a commercial oxygen electrode and 2.0-30.0muM caffeic acid, 2.0-10.0muM ferulic acid, 4.0-30.0muM syringic acid for laccase immobilised on ferrocene-modified screen-printed electrodes. Furthermore, optimal pH, temperature and thermal stability studies were performed with the commercial oxygen electrode. Both electrodes were used for determination of a class of phenolic acids, achieving a cheap and fast tool and an easy to be used procedure for screening real samples of human plasma.

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