Enzymes play a crucial role in chemical reactions within the human body and nature. However, integrating them into electronic devices—such as sensors—remains a challenge, particularly due to difficulties in ensuring efficient electron transfer between enzymes and electrodes using conventional technologies.
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A research team from the University of Tsukuba has recently addressed this issue using metal-organic frameworks (MOFs), a class of materials composed of metal ions and organic linkers that form porous crystalline structures.
While MOFs are commonly used in gas adsorption and separation, they are typically redox-inactive and exhibit poor electrical conductivity. To overcome this limitation, the researchers modified the MOF structure with redox mediators—materials that enhance electron conduction and facilitate specific redox reactions. This modification effectively acts as a "wire," enabling efficient electron exchange between the enzyme and electrode.
Beyond improving conductivity, the MOF design allowed easy access to the enzymes' buried active sites. The researchers also engineered a nanoscale structure and developed an effective immobilization strategy to keep the enzyme securely attached to the electrode surface, minimizing enzyme leaching—a common issue that can lead to inaccurate measurements.
This approach significantly enhances the efficiency and stability of enzyme-based biosensors, enabling long-term, reliable measurements. The findings open up potential applications in fields such as disease diagnosis, environmental monitoring, and sustainable energy technology. The research team hopes their work will not only advance scientific understanding but also lead to practical innovations that benefit society.
Journal Reference:
Rezki, M., et al. (2025) Rational design of redox active metal organic frameworks for mediated electron transfer of enzymes. Materials Horizons.doi.org/10.1039/D4MH01538J