Doctoral Dissertations
Date of Award
12-2024
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Major
Chemistry
Major Professor
David M. Jenkins
Committee Members
Deborah A. Penchoff, Shawn R. Campagna, Sheng Dai
Abstract
Functionalized gold materials serve as the basis of promising new technologies in the biological and biomedical arena. As such, developing scaffolds for gold surface and nanomaterial functionalization that are resistant to degradation and operationally robust is of paramount importance. Thiols are the primary ligands currently utilized for self-assembled monolayers on gold materials. While thiol self-assembly and behavior on surfaces is well-understood, thiols are also highly susceptible to degradation under the conditions necessary for key applications in biomedicine and biosensing. N-heterocyclic carbenes (NHCs) have recently emerged as a contending alternative to thiol self-assembled monolayers for functionalizing gold due to their resistance to degradation and desorption under harsh and oxidative conditions, as well as their stability over wide a range of pHs. NHCs are rapidly advancing the field of functionalized gold materials, and more is being understood about NHC monolayers and their behavior on gold. When targeting these myriad applications, tackling the material requirements for monolayers at the level of synthetic ligand design exploits the modularity of individual NHC ligands for broad utilization. This dissertation undertakes a rational design approach for developing NHCs tailored towards a diverse range of applications, and will focus on the synthesis of NHC precursor species and gold complexes, as well as the spectroscopy, and electrochemical interrogation of NHC-functionalized gold materials towards deepening fundamental understanding and expanding new technologies. Isotopically-labelled NHCs enable fundamental studies of spectroscopy towards determining Au-C stretching modes on nanoparticle surfaces. Varied wingtip structures and NHC precursors allow for optimization of monolayer stability under electrochemical interrogation. Finally, development of a new type of water-soluble NHC shows promise for increased nanoparticle stability in aqueous solutions.
Recommended Citation
Jensen, Isabel Marie, "N-Heterocyclic Carbenes on Gold: Towards Fundamental Understanding and Applications in Biosensing. " PhD diss., University of Tennessee, 2024.
https://trace.tennessee.edu/utk_graddiss/11318
