A strategy to prepare robust enzyme@covalent organic framework microcapsules: a new platform for biosensing

Area of Science:

• Materials Science
• Biotechnology
• Chemical Engineering

Background:

• Enzyme biosensors offer high specificity but suffer from enzyme instability.
• Conventional covalent organic framework (COF) synthesis methods often inactivate enzymes due to harsh conditions.
• Protecting enzymes within COFs is desirable but challenging.

Purpose of the Study:

• To develop a mild and effective strategy for encapsulating enzymes within COFs.
• To create robust enzyme@COFs microcapsules (enzyme@MC_COFs) with enhanced enzyme protection and stability.
• To demonstrate the application of these microcapsules in a glucose biosensing platform.

Main Methods:

• Enzymes were encapsulated using a Pickering emulsion method with hydrophobic COFs spheres.
• COFs regrowth was employed to reinforce the microcapsule shell, providing a mild encapsulation environment.
• The strategy was validated using various hydrophobic COFs and a glucose biosensing platform.

Main Results:

• Achieved an impressive enzyme encapsulation efficiency of 85.9% with minimal enzyme inactivation.
• The resulting enzyme@MC_COFs exhibited mechanical robustness and adjustable pore sizes for efficient substrate transport.
• A predictive formula for controlling microcapsule size was developed.
• A cascade catalytic system was successfully emulated for colorimetric and electrochemical glucose biosensing.

Conclusions:

• The developed interfacial assembly and COFs regrowth strategy offers a simple yet effective method for preparing robust enzyme@COFs microcapsules.
• This approach significantly improves enzyme stability and protection for biosensing applications.
• The enzyme@MC_COFs are versatile and can be tailored for specific requirements, paving the way for advanced biosensor development.