Metal-Organic Frameworks-Based Immobilized Enzyme Microreactors Integrated with Capillary Electrochromatography for...

Area of Science:

• Analytical Chemistry
• Materials Science
• Biochemistry

Background:

• Enzyme assays are crucial for biochemical studies, clinical diagnostics, and drug development.
• Immobilized enzyme microreactors (IMERs) integrated with capillary electrophoresis (CE) are used for online enzyme assays.
• Traditional IMER-CE methods suffer from low loading capacity and poor stability.

Purpose of the Study:

• To explore metal-organic frameworks (MOFs) as novel support materials for IMERs in capillary electrochromatography (CEC).
• To develop a high-efficiency online enzyme assay system using MOF-based IMER-CEC.
• To demonstrate the application of this system for detecting pesticides.

Main Methods:

• Immobilization of acetylcholinesterase (AChE) onto UiO-66-NH2 MOF nanocrystals coated inside a capillary.
• Construction of an integrated MOFs-IMER-CEC microanalysis system.
• Assessment of enzyme kinetics (Michaelis-Menten constant) and inhibition kinetics.
• Separation of neutral, acidic, and basic compounds using the modified capillary.
• Detection of organophosphorus pesticides in vegetable samples.

Main Results:

• The UiO-66-NH2 MOF provided excellent enzyme immobilization with high loading capacity and stability.
• The MOF-based IMER-CEC system exhibited superior affinity for substrates and improved repeatability.
• High-efficiency separation of diverse compounds was achieved.
• The system successfully detected organophosphorus pesticides in real samples.

Conclusions:

• MOFs offer a promising alternative support material for developing high-performance IMERs.
• The MOFs-IMER-CEC system represents a significant advancement for online enzyme assays.
• This approach has broad applicability in bioanalysis and biosensing, including environmental monitoring.