Co-Immobilized Multi-Enzyme Systems with Spatial Arrangement for Glucose Detection

Area of Science:

• Biotechnology
• Biosensors
• Materials Science

Background:

• Traditional random co-immobilization of enzymes for glucose detection lacks spatial control, hindering catalytic efficiency and sensitivity.
• Hydrogen peroxide (H₂O₂) inhibition is a significant challenge in multi-enzyme systems for glucose sensing.
• Hierarchical porous carbon spheres offer a versatile platform for enzyme immobilization.

Purpose of the Study:

• To develop a compartmentalized multi-enzyme system for enhanced glucose detection with precise spatial control.
• To investigate the impact of localized enzyme arrangement on catalytic efficiency and H₂O₂ inhibition.
• To evaluate the stability, reusability, and sensitivity of the developed glucose biosensor.

Main Methods:

• Fabrication of hierarchical porous carbon spheres functionalized with polydopamine (PDA).
• Compartmentalized co-immobilization of glucose oxidase (GOx) and horseradish peroxidase (HRP) within PDA layers on carbon spheres.
• Characterization of enzyme loading, spatial arrangement, and catalytic performance of the HRP.PDA.GOx@NPC-10 system.

Main Results:

• Achieved high immobilization yields for GOx (54.6%) and HRP (65.0%) with controlled spatial localization.
• The HRP.PDA.GOx@NPC-10 system demonstrated 1.65-fold higher activity compared to free enzymes.
• Exhibited excellent stability under extreme pH and temperature, retaining 75.66% activity after 7 cycles.
• Achieved a low glucose detection limit of 0.28 μM with a rapid reaction time of 3 minutes.

Conclusions:

• The compartmentalized enzyme immobilization strategy effectively enhances glucose detection sensitivity and stability.
• The HRP.PDA.GOx@NPC-10 system shows significant potential for practical and sensitive glucose monitoring applications.
• Precise spatial control of enzyme arrangement is crucial for overcoming limitations in multi-enzyme biosensors.