Chemistry Ph.D. Dissertation

Abstract

We explored the diverse applications of supramolecular cages and macrocycles in overcoming complex challenges in the biochemistry and chemical industry, as well as pioneering new possibilities in functional materials. This research is dedicated to discovering the potential of cages/macrocycles as biomimetic anion receptors, industrial absorbance for crucial intermediates, and smart materials towards different stimuli. The results and findings illustrate how these synthetic cages and macrocyclic compounds will interact differently with different guest molecules and provide groundbreaking findings that have practical implications for various industries.

First, a novel crystalized biomimetic cage was introduced as a “protector” to overcome the Hofmeister effect---a phenomenon that interferes with the solubility and function of proteins. The study demonstrated how a synthetic anion receptor can contribute to retaining the activity of lysozyme under conditions where anion-induced precipitation would otherwise inhibit its function.

Second, we addressed alternative methods for separating molecules with close physical properties by utilizing amine-based macrocycles as “separator”, it displays an unique extrinsic/intrinsic approach based on crystal conformation and outlines innovative methods for selective absorption based on different molecular interactions. 

Third, a smart, macrocycle-based “actuator” towards specific organic solvents was synthesized. When these smart macrocycles are exposed to hydrogen bond acceptor solvents, the amorphous compounds become crystallized, and their conformational changes upon the solvent vary at molecular level. Investigation has been done to “amplify” the changes at molecular level to macroscopic level, by composing a macrocycle-contained polymer matrix. It revealed the potential for swift solvent-responsive actuation towards different organic vapors, marking an advancement in the development of "smart" materials that are responsive to external stimuli. This dissertation expands the existing knowledge on the utility of synthetic macrocyclic compounds, suggesting their versatility across multiple applications—from mitigating biological limitations imposed by the Hofmeister effect to chemical separation and the creation of responsive smart materials. The findings presented are not only academically noteworthy but also having significant implications for industrial applications.