Ultra-Thin Self-Assembled Protein-Polymer Membranes: A New Pore Forming Strategy
I recommend we review this article in NRG or journal club – it was just published online in Advanced Functional Materials this week. I see a lot things in this paper that appear to be motivated by our work. They showed SFM/AFM membrane thickness step height, NP gold separations (and cake formation) and water permeation/permeability. Unfortunately for them, it seems they are limited to 50 mbar (<1 psi) even with an underlying support membrane.
Abstract
Self-assembled membranes offer a promising alternative for conventional membrane fabrication, especially in the field of ultrafiltration. Here, a new pore-making strategy is introduced involving stimuli responsive protein-polymer conjugates self-assembled across a large surface area using drying-mediated interfacial self-assembly. The membrane is flexible and assembled on porous supports. The protein used is the cage protein ferritin and resides within the polymer matrix. Upon denaturation of ferritin, a pore is formed which intrinsically is determined by the size of the protein and how it resides in the matrix. Due to the self-assembly at interfaces, the membrane constitutes of only one layer resulting in a membrane thickness of 7 nm on average in the dry state. The membrane is stable up to at least 50 mbar transmembrane pressure, operating at a flux of about 21 000–25 000 L m−2 h−1 bar−1 and displayed a preferred size selectivity of particles below 20 nm. This approach diversifies membrane technology generating a platform for “smart” self-assembled membranes.