Development of an amperometric polyphenol biosensor based on fungal laccase immobilized on nitrocellulose membrane.

A method is described for construction of an amperometric polyphenol biosensor employing nitrocellulose membrane-bound laccase purified from cell-free extract of Ganoderma lucidum onto a Pt electrode. The biosensor showed optimum response within 10s, at 0.4 V in 0.1M acetate buffer, pH 6.0, and 35°C. Detection limit of the biosensor was 3.0 × 10(-8)M. Analytical recovery of added guaiacol was 97.00%. Within batch and between batch coefficients of variation were <0.97% and <1.26%, respectively. The sensor measured total phenolic content in fruit juices and alcoholic beverages. The enzyme electrode was used 100 times over 4 months, when stored at 4°C.