Analysis of Bacterial Adhesion with Graphene Oxide-Modified PES Ultrafiltration Membranes
2019-06
Loading...
View/Download File
Persistent link to this item
Statistics
View StatisticsJournal Title
Journal ISSN
Volume Title
Title
Analysis of Bacterial Adhesion with Graphene Oxide-Modified PES Ultrafiltration Membranes
Authors
Published Date
2019-06
Publisher
Type
Thesis or Dissertation
Abstract
Given its potent biocidal properties, graphene oxide (GO) holds promise as a building block of anti-microbial surfaces, with numerous potential environmental applications. Nonetheless, the extent to which GO-based coatings decrease bacterial adhesion propensity, a necessary requirement of low-fouling surfaces, remains unclear. AFM-based single-cell force spectroscopy (SCFS) was used to show that coatings comprising GO nanosheets bonded to a hydrophilic polymer brush, mitigate adhesion of Pseudomonas fluorescens cells, while preserving GO’s intrinsic biocidal activity. This work demonstrated the simultaneous biocidal and low-adhesion GO coatings by grafting poly(acrylic acid) (PAA) to polyethersulfone (PES) substrates via self-initiated UV polymerization, followed by edge-tethering of GO to the PAA chains through amine coupling. The chemistry and interfacial properties of the unmodified PES, PAA-modified (PES-PAA), and GO-modified PES (PES-GO) substrates were demonstrated using ATR-FTIR, Raman spectroscopy, contact angle goniometry, and AFM to confirm the presence of PAA and covalently bonded GO on the substrates. Using SCFS, it was shown that peak adhesion force distributions for PES-PAA (with mean adhesion force F ̅Peak = -0.13 nN) and PES-GO (F ̅Peak = -0.11 nN) substrates were skewed towards weaker values compared to the PES control (F ̅Peak = -0.18 nN). The results show that weaker adhesion on PES-GO was due to a higher incidence of non-adhesive (repulsive) forces (45.9% compared to 22.2% over PES-PAA and 32.3% over PES), which result from steric repulsion allowed by the brush-like GO-PAA interface.
Description
University of Minnesota M.S. thesis. June 2019. Major: Civil Engineering. Advisor: Santiago Romero Vargas Castrillon. 1 computer file (PDF); vi, 58 pages.
Related to
Replaces
License
Series/Report Number
Funding information
Isbn identifier
Doi identifier
Previously Published Citation
Suggested citation
Wuolo-Journey , Karl. (2019). Analysis of Bacterial Adhesion with Graphene Oxide-Modified PES Ultrafiltration Membranes. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/206163.
Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.