Amperometric Biosensors Based on Direct Electron Transfer Enzymes

Area of Science:

• Electrochemistry
• Biotechnology
• Analytical Chemistry

Background:

• Accurate analyte determination is vital for process control, product analysis, environmental compliance, and medical applications.
• Enzyme-based biosensors offer selective, fast, robust, cost-efficient, and user-friendly devices.
• Direct electron transfer (DET) is a key mechanism for advanced bioelectrocatalysis in biosensors.

Purpose of the Study:

• To review enzymes capable of direct electron transfer (DET) to electrodes.
• To survey electrode materials that enable or enhance DET bioelectrocatalysis.
• To critically evaluate DET-based third-generation biosensors for various applications.

Main Methods:

• Survey of literature reporting DET in enzymes and biosensors.
• Analysis of enzyme types including single/multi-cofactor enzymes with copper centers, hemes, FAD, FMN, or PQQ, and fusion enzymes.
• Review of nanomaterials, nanostructured electrodes, surface modifications, and immobilization strategies for supporting enzyme electrochemistry.

Main Results:

• Identified enzymes and electrode materials that facilitate DET for bioelectrocatalysis.
• Presented amperometric biosensors for quantifying medical, technical, and environmental analytes.
• Evaluated enzyme-electrode combinations based on substrate specificity, current density, sensitivity, and detection range.

Conclusions:

• DET-based biosensors represent a significant advancement in analytical technology.
• Optimized enzyme and electrode materials are essential for high-performance DET biosensors.
• This review provides a critical overview of current progress and requirements for DET biosensor development.