Researchers have developed an oxygen scavenger that consumes excess oxygen by converting it into water. Crucially, this alcohol oxidase does not react with the actual target substances — glucose, creatinine, or lactate. After this “clean-up,” only minimal oxygen remains, allowing the primary oxidase to transfer nearly all its electrons to the sensor.
In a lab study, the accuracy of oxidase biosensors for glucose, lactate, and creatinine was increased from approximately 50 percent to 99 percent — without the need for prior calibration. Lactate, for instance, is measured when monitoring critically ill patients. According to the researchers, this breakthrough opens up entirely new fields of application.
Biosensors are also used for many healthcare areas, but many promising applications require greater precision. For example, measuring creatinine levels, an important indicator of kidney function, has been too inaccurate so far. As a result, the full potential of biosensors remains untapped.
The previous lack of accuracy stems from the way these sensors operate. They use oxidases — enzymes that convert substances like glucose into gluconolactone and electrons. The electrons are transferred to electrodes built into the sensor, generating an electrical current. The higher the concentration of a substance, the stronger the current displayed. The problem: oxidases don’t just transfer electrons to the electrode — they also transfer them to oxygen in the environment. These “lost” electrons don’t contribute to the current, weakening the signal and causing the measured concentration to appear lower than it really is.
To solve this, the researchers developed the oxygen scavenger.
