Anisotropic membranes with carboxypeptidase G1

Area of Science:

• Biomaterials Science
• Enzyme Immobilization Technology
• Biomedical Engineering

Background:

• Developing effective methods for enzyme immobilization is crucial for biocatalysis and therapeutic applications.
• Polysulfone membranes offer a versatile platform for incorporating active biomolecules.
• Extracorporeal removal of methotrexate is a critical therapeutic strategy in certain medical conditions.

Purpose of the Study:

• To prepare and characterize anisotropic polysulfone membranes with embedded carboxypeptidase G1.
• To evaluate the stability and kinetic performance of the immobilized enzyme in hollow-fiber format.
• To assess the potential clinical utility of these membranes for methotrexate detoxification.

Main Methods:

• Anisotropic polysulfone membranes were fabricated via precipitation of polymer solutions containing dispersed carboxypeptidase G1.
• Enzyme activity, leakage, and pH profiles were assessed for both free and immobilized enzyme.
• Kinetic parameters were determined using multitubular enzyme reactors with varying flow rates and substrate concentrations.
• In vitro experiments were conducted using 5000-fiber reactors.

Main Results:

• Successfully prepared enzymatically active anisotropic flat and hollow-fiber membranes with carboxypeptidase G1.
• Demonstrated no detectable enzyme leakage from the hollow-fiber membranes upon perfusion.
• Observed similar pH profiles for free and embedded carboxypeptidase G1.
• Identified significant mass transfer effects influencing observed kinetics in enzyme reactors.

Conclusions:

• The developed polysulfone hollow-fiber membranes provide a robust system for carboxypeptidase G1 immobilization.
• These membranes exhibit excellent enzyme retention and stability, suitable for continuous flow applications.
• The findings support the clinical potential of these hollow-fiber cartridges for extracorporeal methotrexate removal.