A universal oxygen scavenger for oxidase-based biosensors

Oxidase-based electrochemical biosensors are widely deployed for point-of-use applications, yet oxygen interference remains a major challenge, substantially reducing sensing accuracy. Here, we developed a universal enzymatic O2 scavenger composed of alcohol oxidase, catalase, and paraformaldehyde to eliminate O2 within the sensor by converting it to water. Unlike other oxidases, alcohol oxidase exclusively uses O2 as an electron acceptor, preventing interference with the electron transfer chain involving the sensing oxidase. We demonstrated the compatibility of this O2 scavenger for calibration-free sensing of glucose, lactate, and creatinine in the concentration range relevant to human health. Without the O2 scavenger, sensor readings were less than 50% of those under inert gas conditions. With the O2 scavenger, the accuracy improved to 99%, even at low substrate concentrations. The general compatibility and performances of this alcohol oxidase-based O2 scavenger unlock the full potential of oxidase-based biosensors for reliable point-of-use sensing.     «

Oxidase-based electrochemical biosensors are widely deployed for point-of-use applications, yet oxygen interference remains a major challenge, substantially reducing sensing accuracy. Here, we developed a universal enzymatic O2 scavenger composed of alcohol oxidase, catalase, and paraformaldehyde to eliminate O2 within the sensor by converting it to water. Unlike other oxidases, alcohol oxidase exclusively uses O2 as an electron acceptor, preventing interference with the electron transfer chain...     »