An electrokinetic approach to fabricating aquaporin biomimetic membranes for water purification

Membrane technology has been dominating the water desalination industry for decades due to its high efficiency and reliability. However, conventional membrane materials present performance limitations; thus, the demand for the development of new material is high. In recent years, aquaporin biomimetic membranes have emerged as a next-generation water desalination platform based on natural phenomena. Aquaporin is a natural water-selective protein that possesses exceptional water selectively and permeability properties. However, aquaporin must be embedded in an amphiphilic structure, such as a cell membrane, and the mimetic structure and stability of these environments represent key factors for successful water purification systems. Herein, we report an electrokinetic approach that stabilizes the aquaporin-containing membranes on a porous substrate under an applied electric field, resulting in an exceptionally stable and uniform biomimetic membrane on a solid support. The surface morphological analysis shows that the liposomes retained their perfect shape and size and did not present fusion or aggregation. Moreover, under forward osmosis, our membrane presents a salt rejection rate that reached 97.8 ± 0.7% with 7.45 ± 0.62 Lm⁻²h⁻¹ (LMH) of water flux.