Self-powered cathodic detection of dissolved oxygen using a paper-based biofuel cell

Abstract

Herein we report the self-powered biosensor for detection of dissolved oxygen (DO) detection using a paper-based enzymatic biofuel cell (BFC) employing screen-printed electrodes composed of MgO-templated mesoporous carbon (MgOC). The sensor used an anode modified by flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH) and a cathode modified by bilirubin oxidase (BOD) to enable selective oxygen reduction under glucose-rich conditions. Electrochemical analyses revealed a linear relationship between the cathodic current and DO concentration over the range of 0–22 mg L⁻¹, with a maximum power output of 398 µW cm⁻² at 20 mg L⁻¹ DO. The biosensor system was successfully used to quantify DO in both pure water and a commercial soft drink, without requiring external power sources. These findings demonstrate the feasibility of low-cost, disposable, and scalable DO sensing by using cathode-targeting enzymatic BFCs, thereby opening new avenues for environmental and food quality monitoring.