Horseradish Peroxidase Combined With Oxidase Enzymes a Valuable Bioanalytical Tool: Lactate Oxidase - A Case Study

Enzymatic biosensors have been extensively investigated for real‐time bioprocess monitoring and other online analysis. However, implementation of biosensors has been strongly hindered by their limited stability. This work reports a significant improvement of the stability of the immobilized oxidases by in situ reduction of the harmful H2O2. Thus, stabilized oxidases can serve as the basis for ethanol, glucose, and lactate sensors, with the ability to operate for long periods of time with virtually no change in activity. As an example, a lactate sensor, containing lactate oxidase aimed for bioprocess monitoring, has been described and characterized. Operational stabilities that allow up to 8 h continuous lactate conversion with virtually no activity loss have been achieved. The described system based on the in situ stabilization strategy is a promising new tool for the development of online analyses. A significant improvement of the stability of the immobilized oxidases by in situ reduction of the harmful H2O2 is reported. A lactate sensor, containing lactate oxidase aimed for bioprocess monitoring, has been described and characterized. Operational stabilities have been achieved that allow up to 8 h continuous lactate conversion with virtually no activity loss.