A laccase-based biosensor was developed by specific enzyme adsorption on screen-printed working electrodes of DROPSENS cells, and stabilized with Nafion 0.1% membrane. The electrode was characterized with respect to response time, sensitivity, linear range, detection limit, pH dependence, interferences, and long-term stability. The tested substrates were catechol, rosmarinic acid, caffeic acid, chlorogenic acid, and gallic acid. The optimized biosensor proved the following characteristic performances: the apparent Michaelis Menten calculated considering rosmarinic acid substrate 8.3 × 10-6 mol L-1 (r = 0.995, n = 6); the dynamic range of biosensor response for rosmarinic acid 7 × 10-7 - 1.5 × 10-6 mol L-1; the detection limit for rosmarinic acid 1.19 × 10-7 mol L-1 (RSD = 1.08%, n = 3). It was noticed that the biosensor reaches systematically 90% to 94.3% from the response obtained by LC-DAD-ESI-MS for real samples.
|Autori:||Litescu; Simona; Eremia; Sandra; Bertoli A; Pistelli; Luisa2; Radu; Gabriel-Lucian|
|Titolo:||Laccase-Nafion Based Biosensor for the Determination of Polyphenolic Secondary Metabolites|
|Anno del prodotto:||2010|
|Digital Object Identifier (DOI):||10.1080/00032710903518518|
|Appare nelle tipologie:||1.1 Articolo in rivista|