Development of a glucose sensor employing quick and easy modification method with mediator for altering electron...

Area of Science:

• Electrochemistry
• Biosensors
• Enzyme Engineering

Background:

• Enzyme-based electrochemical biosensors are classified into three generations based on electron transfer mechanisms.
• Third-generation sensors ideal for direct electron transfer (DET) are limited by the scarcity of suitable enzymes.
• A need exists for broader applicability of enzyme-based biosensors through enhanced electron transfer capabilities.

Purpose of the Study:

• To develop a novel glucose sensor utilizing mediator-modified glucose dehydrogenase (GDH) with enhanced electron transfer properties.
• To establish a "2.5th generation" biosensor platform enabling quasi-direct electron transfer (quasi-DET).
• To demonstrate the adaptability of this approach for various diagnostically relevant enzymes.

Main Methods:

• Fabrication of a glucose sensor using pre-functionalized amine reactive phenazine ethosulfate (arPES) to modify GDH.
• Immobilization of PES-modified GDH onto electrodes for glucose detection.
• Modification of other enzymes, including glucoside 3-dehydrogenase and lactate oxidase, with PES.

Main Results:

• Mediator-modified GDH demonstrated the ability to transfer electrons to electrodes without external mediators.
• Successful glucose concentration measurement using immobilized PES-modified GDH.
• PES modification successfully imparted quasi-DET ability to glucoside 3-dehydrogenase and lactate oxidase.

Conclusions:

• The developed "2.5th generation" biosensor principle utilizing quasi-DET overcomes limitations of traditional sensor generations.
• The quick-and-easy arPES modification method allows various enzymes to achieve quasi-DET.
• This platform holds significant potential for developing continuous monitoring systems for diverse target molecules.