Evaluation of membranes for plasmapheresis

Area of Science:

• Biomedical Engineering
• Membrane Science
• Hematology

Background:

• Plasmapheresis requires efficient blood filtration membranes.
• Microporous membranes are candidates for plasmapheresis devices.
• Understanding filtration dynamics is crucial for optimizing performance.

Purpose of the Study:

• To evaluate commercial flat-sheet microporous membranes for plasmapheresis.
• To investigate factors affecting filtration rates and membrane capacity.
• To assess membrane interaction with plasma proteins and clotting factors.

Main Methods:

• Filtration experiments using saline, cell-free plasma, platelet-poor plasma, and whole blood.
• Perfusion of various membranes in a specially designed filtration module.
• Measurement of filtration rates and analysis of protein rejection and clotting factor activation.

Main Results:

• Significant differences in filtration rates were observed across different membranes.
• Saline filtration did not predict plasma filtration capacity.
• No plasma protein rejection or significant clotting factor alteration occurred.
• Cell-free plasma filtration rate decreased over time due to protein adsorption.
• Whole blood filtration rates were significantly lower than cell-free plasma, limited by cell layer formation (particle polarization).

Conclusions:

• Flat-sheet microporous membranes are suitable for plasmapheresis regarding protein and clotting factor integrity.
• Particle polarization, the formation of a blood cell layer on the membrane surface, is the primary limitation for blood filtration rates.
• Membrane selection and module design should account for cell layer formation to optimize plasmapheresis efficiency.