Abstract

Rapid electrochemical quercetin detection by oxidation of oxygen from laccase-quercetin enzymatic reaction from Trametes versicolor is proposed. Three different method for laccase enzyme immobilization on screen printed carbon electrode (SPCE) were compared for the development of quercetin biosensors. In this work, gluteraldehyde and nafion were deposited onto enzyme electrode surface and were evaluated by cyclic voltammetric and chronoamperometric. The measurements were performed in 0.05M acetate buffer (pH 5.0). The modified biosensor for quercetin detection based on laccase/gluteraldehyde/SPCE gives highest sensitivity (341.2µAmM-1cm^-2) at concentration of laccase (100mgmL^-1) and at applied potential +0.2V. The range of detection is from 1.0 to 20.0 µM (R²=0.99) with a detection limit of 3.74µM and response time of 2.45s. 

Keywords

biosensor, quercetin, SPCE, laccase, cyclic voltammetric, chronoamperometric