There is widespread use of ionization sources (ambient and non-ambient)
for a variety of applications. More recently, charged microdroplets generated
by electrospray ionization and paper spray have been used to conduct chemistry
at faster rates compared to bulk volumes. Uncharged droplets such as those
generated by the Leidenfrost technique have also been used to explore chemistry
and study the degradation of drugs in an accelerated manner. These
microdroplets serve as reaction vessels in which in which some reactions are
known to occur at accelerated rates. Such chemistry can be particularly useful
in pharmaceutical settings to rapidly synthesize small amounts of materials in
relatively short amount of time. Additionally, microdroplets may also be used
to perform high throughput screening analysis. While several parameters
influencing the rate of reaction in microdroplets have been explored (such as
spray distance and reagent concentration), the mechanism of reaction
acceleration has not been probed to a significant extent. A major portion of my
dissertation describes the use of charged and uncharged microdroplets to
perform quick chemistry, guide microfluidic synthesis of drugs such as diazepam,
perform scale up of copper catalyzed C-O and C-N coupling reactions and screen reaction conditions for pharmaceutically
relevant reactions such as the Suzuki cross-coupling reaction. Additionally,
work discussed here also describes development and use of existing techniques
such as structured illumination microscopy to measure droplet sizes, explore
the role of distances on droplet size, and study the effect of surfactants on
the rate of reactions in microdroplets generated by nano-electrospray
ionization. A mathematical model to understand the mechanism of increased
reaction rates in microdroplets has also been presented. Additionally, this
dissertation also describes ways to manipulate ions in air using various
designs of 3D-printed electrodes that operate with DC potentials only and which
can be easily coupled with nano-electrospray ionization sources to transmit
ions over long distances