A mediated turnip tissue paper-based amperometric hydrogen peroxide biosensor

A novel inexpensive turnip tissue paper-based mediated amperometric hydrogen peroxide (H2O2) biosensor was developed based on screen-printed carbon electrodes (SPCEs). The use of cellulose paper proved to be an ideal and simple biocompatible immobilization matrix for raw turnip peroxidase as it was successfully embedded within the fiber matrix of paper via physical adsorption. The mediator potassium hexacyanoferrate (II) was also embedded onto the paper matrix together with the raw enzyme. The biosensor allowed a minute amount (0.5 mu L) of sample solution for analysis. The linear calibration range of the biosensor was between 0.02 and 0.50 mM (R-2= 0.999) with a detection limit of 4.1 mu M H2O2, calculated based on IUPAC convention. Its analytical performance was demonstrated in real sample analysis and the results obtained corroborated well with the classical titration method. Without any complex packaging modification, the biosensor retained ca. 70% of its activity after a storage period of 25 days at 4 degrees C. (C) 2015 Elsevier B.V. All rights reserved.