(593c) Development of Biomimetic Reverse Osmosis Membranes Via Molecular Self-Organization of Phospholipid Bilayer

Biomimetic separation membranes have been attracting attention as future water treatment membranes such as reverse osmosis and forward osmosis^1,2). The biomimetic membrane can transport target molecules highly effectively and selectively. In this study, we demonstrate two approaches to prepare biomimetic water treatment membranes via molecular self-organization. One is using electrostatic interaction between a polyamide support membrane and cationic liposomes (Figure 1A). The polyamide membrane was immersed into the cationic liposome suspension, and the liposomes were adsorbed onto the membrane. By pressurized at given pressure, the adsorbed liposomes were transformed into a flat bilayer structure. The prepared membrane showed higher salt rejection enough to use of a RO membrane process. Furthermore, addition of gramicidin A as a water channel molecule into the liposomes improved the water permeability. The other is using hydrophobic interaction between an alumina support membrane and liposomes. The alumina membrane was hydrophobilized by a silane coupling agent and immersed into the liposome suspension, and lipid bilayers were spontaneously formed onto the alumina membrane. The bilayer formation was confirmed by a fluorescence recovery after photobleaching (FRAP) method. The prepared membrane via hydrophobic interaction also showed higher salt rejection. These results indicate that the two presented approaches could be applicable to fabrication of new structural water treatment membranes.

References

1. Y. Kaufman, et al., Langmuir, 26, 7388 (2010).

2. H.L. Wang, et al., Small, 8, 1185 (2012).