Investigation of optoelectronic properties and anti/pro-oxidation effects of carbon nanodots (CNDs) doped with different heteroatoms
- UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
- Mahsa Azami (Creator)
- Institution
- The University of North Carolina at Greensboro (UNCG )
- Web Site: http://library.uncg.edu/
- Advisor
- Jianjun Wei
Abstract: Owing to unique characteristics, such as low toxicity, outstanding biocompatibility, intrinsically strong photoluminescence, as well as facile synthesis, carbon nanodots (CNDs) have recently been the focal point of different fields of research. However, a full understanding of their potential properties and mechanisms is yet to be achieved. This dissertation focuses on the impacts of doping with two heteroatoms, phosphorus (P) and boron (B), on three major features of CNDs: optoelectronic properties, oxidative stress effects at cellular and genomic levels, and an optical sensing application. First, we reviewed the cellular uptake, sub-cellular localization, cytotoxicity, and oxidative stress effects of CNDs in cells, and their contributing mechanisms in different diseases associated with oxidative stress. In the second part of this dissertation, different amounts of P and B are incorporated into the structures of CNDs to examine their influence on the optical and anti-oxidation capabilities. Both dopants can increase light absorption and fluorescence, yet in differing ways. In addition, both dopants can boost the radical scavenging capabilities of CNDs in physicochemical conditions. In the third part of our study, we examined the effects of N, P-CNDs and N, B-CNDs on oxidative stress in normal and cancer cell lines. Using cytotoxicity tests, we attempted to determine the safe concentration range of these CNDs for further biological applications. At varying concentrations, these CNDs behaved differently in terms of their ability to scavenge free radicals, e.g., reactive oxidative species (ROS), in living cells. To study potential genomic effects, we selected three genes associated with anti-oxidation and evaluated the changes upon N,P-CNDs and N,B-CNDs treatment on the expression levels of these genes in both normal and cancer cell lines. The results indicated that effects and outcomes at the genomic level could differ from those at the cellular level. Overall, it was concluded that both introduced CNDs induced oxidative stress in cancer cells which can be used as effective tools in the direction of pro-oxidant therapy in cancer. However, their final fate in normal cells demonstrated plausible pro-oxidant effects, which needs to be addressed by precise delivery of the agent to cancer cells. Finally, we examined the selectivity and sensitivity of highly fluorescent N,B-CNDs as an optical probe for the detection of Fe2+ in water samples. We also looked at the bioimaging capabilities of these CNDs for Fe2+ detection in living cells. With the addition of iron ions, the fluorescence intensity of the CNDs diminishes in a concentration-dependent way, which can be attributed to the charge transfer between the CNDs and Fe2+, as confirmed by electrochemical testing and band-gap energy analysis. Therefore, these CNDs could serve as effective “Turn–Off” fluorescence-based probes for Fe2+ detection. Overall, the findings from this dissertation work pave a way to understanding the underlying mechanisms of heteroatom doping effects on tuning the structural and optoelectronic features of CNDs, and their contribution to oxidative stress-related disorders at cellular level. [This abstract may have been edited to remove characters that will not display in this system. Please see the PDF for the full abstract.]
Investigation of optoelectronic properties and anti/pro-oxidation effects of carbon nanodots (CNDs) doped with different heteroatoms
PDF (Portable Document Format)
5105 KB
Created on 5/1/2023
Views: 9
Additional Information
- Publication
- Dissertation
- Language: English
- Date: 2023
- Keywords
- Carbon nanodots, Dopant heteroatoms, Gene expression, Oxidative stress, ROS scavenging, Sensor
- Subjects
- Nanostructured materials $x Optical properties
- Oxidative stress
- Gene expression