Date of Award
1-1-2023
Document Type
Dissertation
Degree Name
Ph.D. in Chemistry
First Advisor
Jared H. Delcamp
Second Advisor
Nathan I. Hammer
Third Advisor
Eden E. L. Tanner
Relational Format
dissertation/thesis
Abstract
Low energy light in the near infrared (NIR, 700 – 1000 nm), shortwave infrared (SWIR, 1000 – 1700 nm), and extended SWIR (ESWIR, 1700 – 2700 nm) has numerous important applications including fluorescence biological imaging, secure display technologies, and photodetectors. While inorganic materials have dominated each of these spectral regions, organic molecules that absorb and emit light in these regions are being heavily researched due to their high degree of molecular tunability via structure-function relationships, cheap production due to the avoidance of precious metals, ease of manufacturing through solution processability, and operation under physiological and ambient conditions. This dissertation illustrates advancements in the design, synthesis, characterization, and application of low energy absorbing organic molecules in the NIR, SWIR, and ESWIR. First, NIR emitting sulfonate indolizine squaraine and cyanine dyes (SO3SQ and SO3C5) are shown to be potent binders to albumin, the most abundant protein in blood serum, with record setting fluorescence quantum yields for their respective spectral regions. Second, a series of SWIR emitting indolizine xanthene fluorophores with a silicon core (SiRos) are optimized for their stability and photophysical properties via structural modifications, generating the lowest energy emitting organic fluorophores in the literature. The optimized fluorophores are subsequently used to generate high resolution in vivo SWIR images past 1500 nm and demonstrate utility for multiplex imaging. Lastly, a series of antiaromatic indolizine fluorenium dyes (FluIndz) are synthesized and observed to exhibit absorption maxima in the ESWIR, generating some of the lowest energy absorbing organic chromophores in the literature to date. These discoveries illustrate noteworthy photophysical advancements in each of these spectral regions and establish impactful design principles for future low energy absorbing and emitting organic molecules.
Recommended Citation
Meador, William E., "Design, Synthesis, and Application of Indolizine-Donor Containing Fluorophores for Near-Infrared and Shortwave-Infrared Biological Imaging" (2023). Electronic Theses and Dissertations. 2761.
https://egrove.olemiss.edu/etd/2761