Abstract:
This dissertation is a synopsis of advancements in the field of ionic liquids and a group
of uniform materials based on organic salts (GUMBOS) in biomedical applications, especially
with regard to cancer research. The toxicity of chemotherapeutic agents to normal tissues and
drug resistance are a major concern in cancer treatment. In this dissertation, GUMBOS and
nanoGUMBOS as well as ionic liquids and nanodroplets are explored as possible
chemotherapeutic agents with minimal toxicity to normal cells.
In the first part of my dissertation, exploitation of ionic liquid chemistry to modulate
toxicity of rhodamine 6G is reported. Rhodamine 6G-based GUMBOS with varying counter-
anions that are stable under physiological conditions, display excellent fluorescence
photostability, and more importantly have tunable chemotherapeutic properties were
synthesized. In vitro studies indicate that the hydrophobic compounds of this series allow
production of nanoGUMBOS which are non-toxic to normal cells and toxic to cancer cells.
Furthermore, the anions, in combination with cations such as sodium, were observed to be
non-toxic to both normal and cancer cells. Thus, we demonstrate that both the cation and
anion play an extremely important and cooperative role in the anticancer properties of these
compounds.
In the second part, the concept of multifunctional nanoparticles is introduced and
exploited for theranostic applications. Nanoparticles possessing multiple properties such as
luminescence, magnetism, and cancer targeting, were synthesized and explored for use in
cancer therapy. In this regard, it is demonstrated that these nanoparticles can not only be used
in diagnostics and as drug delivery agents, but also as active pharmacophores.
Finally, the third part of this dissertation is a report of novel ionic liquid based pH
sensitive colorimetric nanosensors based on phosphonium and fluorescein. The pH dependent size changes in the nanodroplets are demonstrated and potential applications in detecting
acidic environment and anticancer activity are investigated.