Aquaporin-Containing Proteopolymersomes in Polyelectrolyte Multilayer Membranes

Area of Science:

• Materials Science
• Biomimetic Engineering
• Membrane Technology

Background:

• Recent advancements in membranes include polyelectrolyte multilayer (PEM)-based and biomimetic membranes.
• Proteopolymersomes (PP+) incorporate aquaporin proteins, offering potential for enhanced membrane functionality.

Purpose of the Study:

• To fabricate and characterize proteopolymersome multilayers (PPMs) on hollow fiber membranes by combining PEM and biomimetic approaches.
• To investigate the influence of different polyanions (PSS and PAA) on PPM structure, stability, and separation performance.

Main Methods:

• Fabrication of PPMs using PP+ with poly(styrene 4-sulfonate) (PSS) or poly(acrylic acid) (PAA) via layer-by-layer adsorption.
• Characterization using reflectometry and scanning electron microscopy (SEM).
• Evaluation of membrane permeability and salt retention (MgSO4, MgCl2, Na2SO4) for different PPM compositions.

Main Results:

• PSS-based PPMs exhibited stable vesicular structures and good layer growth, unlike dewetted PAA-based PPMs.
• PSS/PP+ membranes showed improved MgSO4 retention (80%) and selective salt separation (Donnan-exclusion behavior), while PAA/PP+ layers were defective.
• The charge within the multilayer could be tuned by using PP+ instead of a polycation, altering separation behavior.

Conclusions:

• Combining PEMs and biomimetic systems, specifically PSS/PP+ PPMs on hollow fiber membranes, yields promising results for membrane applications.
• This approach offers versatility for both PEM and biomimetic membrane systems, achieving desired performance in a hollow fiber geometry.
• The study demonstrates the potential of proteopolymersomes in creating advanced separation membranes with tunable properties.