Author ORCID Identifier
Document Type
Dissertation
Date of Award
2024
Degree Name
Doctor of Philosophy (PhD)
Department
Chemistry
First Advisor
Grigoriy Sereda
Abstract
Biofilms are surface-attached microorganism communities that are embedded in extracellular matrix. They play a significant role in different infections which cause many life-threatening diseases in the world population. Many strategies have been developed to control biofilm formation and microbial adhesion on the surface such as coating by an antimicrobial agent, chemical modification of surfaces, and physical destruction of biofilm areas. However, these techniques are not sufficient to limit the widespread biofilm formation. Therefore, new antimicrobial strategies need to be developed to control these often antibiotics-resistant microorganisms. The aim of our work is to develop novel materials to maximize the capability of pristine and defective monolayer graphene to control biofilm formation. We functionalized pristine monolayer graphene using homocysteine as a thiol followed by silver nanoparticles deposition. Homocysteine is one of the quorum sensing molecules which can enhance biofilm formation and silver nanoparticles are known microbial agents. We have shown that quorum sensing molecules will attract bacterium cells and the sharp edges of graphene will act as nano-blades to cut the membrane of microorganisms causing the leakages of cytoplasmic constituents, which kills them. Besides, the properties of pristine monolayer graphene can be tailored by introducing small amounts of defects in a very controllable manner. An exposure to oxygen plasma was used to generate defects on Cu-supported pristine monolayer graphene and sodium thiosulfate was used to stain those defective sites. Therefore, functionalized pristine monolayer graphene materials combined with a quorum sensing agent may lead to the development of new antimicrobial materials. We have also synthesized graphene microparticles by exfoliative functionalization of graphite with synthesized organic linker molecules via 1,3-dipolar addition and silanization. Additionally, we have investigated Surface Enhanced Raman Spectroscopy (SERS) of graphene with organic molecules, such as thymine, to broaden the methods for functionalization.
Subject Categories
Chemistry
Keywords
BIOFILMS
Number of Pages
122
Publisher
University of South Dakota
Recommended Citation
Tusar Uddin, Md, "FUNCTIONALIZATION OF PRISTINE AND DEFECTIVE MONOLAYER GRAPHENE TO CONTROL BIOFILM GROWTH" (2024). Dissertations and Theses. 228.
https://red.library.usd.edu/diss-thesis/228