CUSTOM ANGSTROM-SCALE SEPARATIONS WITH HIGHLY PERMEABLE BIOMIMETIC MEMBRANES

Open Access
Author:
Prabhakar, Jeevan
Area of Honors:
Chemical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Manish Kumar, Thesis Supervisor
  • Darrell Velegol, Honors Advisor
Keywords:
  • OmpF
  • Membranes
  • Biomimetic
  • Desalination
  • Separations
  • PoreDesigner
  • Mutant
  • Filtration
  • Genetic
  • Aquaporin
  • TEM
  • Angstrom
  • E. coli
  • Purification
  • Proteoliposome
Abstract:
There currently exists no process capable of producing thin films with uniform pore size in the 2-10 Angstrom range. These films would have application in water desalination, food processing, industrial gas separations, carbon capture, and biopharmaceutical separations. The goal of this project was to produce biomimetic membranes with uniform pore size capable of performing Angstrom-scale separations with 0.2-Angstrom resolution. Outer membrane protein F (OmpF) was chosen as the scaffold for this project due its unmodified pore size of ~10 Å, number of mutable pore-lining residues, high water permeability, and ability to self-assemble into lipid bilayers. Wild type (WT) OmpF, as well as two other mutants, referred to as TRP OmpF and Trans OmpF, were expressed in E. coli, purified, assembled in lipid vesicles, and tested for permeability and solute rejection via a stopped-flow light scattering technique. Mutant OmpF packed micron scale 2D sheets in block copolymers were produced and characterized by transmission electron microscopy (TEM). Experimental results of mutants show the ability to increase permeability of the protein while maintaining selectivity or to increase selectivity while maintaining permeability.