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Date of Award
2026
Document Type
Campus Access Dissertation
Degree Name
Doctor of Philosophy in Chemistry (PhD)
Administrative Home Department
Department of Chemistry
Advisor 1
Marina Tanasova
Committee Member 1
Ashutosh Tiwari
Committee Member 2
Shiyue Fang
Committee Member 3
Sriram Vijayan
Abstract
Quantitative fluorescence imaging of mitochondrial pH in living systems provides a powerful approach to understanding cellular metabolism, signaling, proliferation, and death. This work presents the development of novel fluorescent probes based on rhodamine, cyanine, and triphenyl acrylonitrile scaffolds for in vitro and in vivo mitochondrial pH monitoring during mitophagy and cellular stress. A series of rhodamine- and triphenyl acrylonitrile-derived fluorophores was rationally designed to exhibit nearinfrared fluorescence emission shifts in response to protonation and deprotonation, enabling real-time visualization of mitochondrial pH dynamics in HeLa cells and Drosophila melanogaster. The developed probes demonstrate excellent sensitivity, selectivity, photostability, reversibility, and minimal cytotoxicity, establishing them as effective tools for investigating mitophagy and mitochondrial dysfunction associated with disease progression.
The second part of this dissertation focuses on the synthesis, characterization, and electrochemical evaluation of a yttrium-based electrocatalyst. The effect of metal-ion incorporation on the structural, morphological, and electrochemical properties of the yttrium phosphide system was studied. The optimized material exhibits outstanding HER and OER electroactivity in alkaline media, characterized by low overpotentials, favorable Tafel slopes, and excellent long-term stability. Notably, the catalyst delivers a current density of 100 mA cm⁻² at a cell voltage of only 1.56 V, highlighting its promise for sustainable hydrogen production. Overall, this dissertation addresses the key challenges in the optimization of phosphide-based electrocatalysts for hydrogen energy applications.
Recommended Citation
Pandey, Subash, "DESIGN, SYNTHESIS, AND APPLICATION OF FLUORESCENT PROBES FOR MITOCHONDRIAL pH MONITORING AND DESIGN AND ELECTROCHEMICAL INVESTIGATION OF Fe-DOPED YTTRIUM OXIDE, PHOSPHIDE, AND MOF-DERIVED ELECTROCATALYSTS FOR WATER SPLITTING: A TWO-PART DISSERTATION", Campus Access Dissertation, Michigan Technological University, 2026.
https://digitalcommons.mtu.edu/etdr/2163