Development and Characterization of Biomimetic Membranes for use in Environmental and Biomedical Applications

Open Access
- Author:
- Jones, Cory Armand
- Graduate Program:
- Chemical Engineering
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- February 09, 2018
- Committee Members:
- Manish Kumar, Thesis Advisor/Co-Advisor
Phillip E Savage, Committee Member
Andrew Zydney, Committee Member - Keywords:
- Biomimetics
Membranes
Opsins
Graphene - Abstract:
- Biomimetic membranes have a variety of applications in the environmental and biomedical realms. The focus of this work is on understanding transport of two types of membranes: 1) Lipid vesicle membranes with incorporated microbial opsins, proteins which pump ions in response to light. 2) Porous Graphene membranes modified with a lipid bilayer. Protein incorporated membranes are important for use in optogenetics. Stopped-flow and patch clamp are two measurement techniques used to characterize ion transport. Stopped-flow was limited in measuring ion activity due to limitations in commercial sodium fluorophores. Patch Clamp was found to be a viable alternative in measuring channel and pump activity of proteins embedded in Giant Unilamellar Vesicles (GUVs) grown through electroformation. Lipid modified graphene membranes were created for use in water desalination. Measurement techniques were developed to accompany a purpose-built diffusion cell which can accurately measure water permeability (A value) and salt permeability (B value). The A and B values were calculated for Forward Osmosis (FO) membranes, and are comparable to industry standards, confirming the ability of this technique to analyze other membranes. An estimate of past unmodified and modified lipid for the A and B values were made by normalizing the number and size of pores. Lipid modified membranes are estimated to provide an A value of 15.7 LMH/bar ((L/(m2 hr))/ bar) (40x increase), B value of 0.0047 LMH (64x decrease), and Water Flux of 26.3 LMH (1.5x increase) in comparison to FO membranes.