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This dissertation elucidates a greater understanding of the vaporization and electrospray post-ionization mechanisms when using femtosecond laser pulses for desorption of surface molecules and electrospray ionization for capture and mass analysis of the gas phase ions. The internal energy deposition from nonresonant vaporization with femtosecond laser pulses was measured using dried and liquid samples of p-substituted benzylpyridinium ions and peptides. In the comparison of the experiments of using 800 nm and 1042 nm laser pulses, it was found that there are different vaporization mechanisms for dried and liquid samples. It was established that LEMS is a "soft" mass analysis technique as it resulted in comparable internal energy distributions to ESI-MS with one caveat; multiphoton excitation of dried samples results in extensive fragmentation at higher pulse energies. The quantitative aspects of the laser electrospray mass spectrometry (LEMS) technique were established using various multicomponent mixtures of small biomolecules. Experiments with LEMS resulted in similar quantitative characteristics to ESI-MS except that ESI-MS demonstrated a greater degree of ion suppression when using higher concentrations, particularly in the four-component mixture. The lack of ion suppression in the LEMS measurements was due to the ~1% neutral capture efficiency and most likely not a result of nonequilibrium partitioning. This was supported by the excess charge limit not being surpassed in the LEMS experiments and the quantitative analysis requiring the use of response factors. This dissertation also expanded upon the use of multivariate analysis for the classification of samples that were directly mass analyzed without any sample preparation using LEMS. A novel electrospray complexation mixture using cationic pairing agents, a lipid, and sodium acetate enabled the simultaneous detection of positive, neutral and negative charged features of inorganic-based explosive residues in a single experiment. This complexation mixture also enabled the detection of new features from an RDX-based propellant mixture. Principal component analysis (PCA) proved reliable for accurate classifications of the explosive mixtures. PCA was also used for accurate classification of eight phenotypes of Impatiens plant flower petals after mass analysis with LEMS. The PCA loading values were used to identify the key biomarkers in the classification. These important mass spectral features were identified as the biologically-relevant anthocyanins, which are phytochemicals that are responsible for the color of the flower petals. / Chemistry

Cancer cells that survive chemotherapy treatment often develop resistance to the administered chemotherapeutics, as well as to many other types of drugs, because the cancer cells increase their production of efflux pumps in the cell. This undesired phenomenon of resistance to cancer drugs is known as multidrug resistance. This work uses a novel drug carrier, called an eLiposome, to achieve cytosolic drug delivery to kill multidrug-resistant cancer cells. An eLiposome consists of a perfluoropentane (PFC5) emulsion droplet inside of a liposome. Folate attached to the eLiposome facilitates uptake into the cell. The PFC5 droplet is metastable at body temperature, but will rupture the liposome as the droplet expands during vaporization, and will release any drugs encapsulated inside of the liposome directly to the cell cytosol. Laser and ultrasound were examined as triggers to initiate the vaporization of the PFC5 droplet and actuate the release of doxorubicin (Dox) from folated eLiposomes containing Dox (feLD). Gold nanorods (GNRs) were synthesized and transferred to PFC5 droplets. Although GNRs are efficient at converting irradiated laser light to heat, no vaporization of the PFC5 droplets was observed when irradiated with laser light. Further investigation into the energy required for vaporization of PFC5 droplets revealed that there are currently no portable and wearable lasers available to provide enough energy to vaporize PFC5 droplets. Two seconds of ultrasound can release 78% of encapsulated Dox from feLD. Dox-sensitive KB-3-1 cells and Dox-resistant KB-V1 cells treated with feLD (without ultrasound) had cell viabilities of 33% and 60%, respectively. Ultrasound had negligible additional effect on the cell viability of KB-3-1 and KB-V1 cells treated with feLD (33% and 53%, respectively). We hypothesized that the Dox fiber formed during the loading of Dox into the eLiposome is a site for heterogeneous nucleation once the feLD is endocytosed by the cell, and vaporization and drug release occurs with or without ultrasound. Blocking the efflux pumps with verapamil decreases the rate at which Dox is exported from multidrug-resistant cells. When verapamil is co-delivered with feLD, the cell viability of KB-3-1 and KB-V1 cells decreases to 29% and 25%, respectively; thereby reversing the multidrug resistance possessed by KB-V1 cells. The delivery of doxorubicin inside of folated eLiposomes with an efflux pump blocker is a novel way to kill multidrug-resistant cancer cells as effectively as non-resistant cancer cells independent of lasers or ultrasound.

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Alternative fuels are becoming more important as fossil fuels become more expensive. This thesis describes the production and properties of a bio-oil produced from waste biomass, in this case chicken litter. A higher quality fuel was produced through thermal and chemical upgrading of the raw bio-oil; this fuel is similar in some respects to fossil fuels, as it has a high hydrocarbon content and energy density comparable to gasoline. Combustion of liquid fuels commonly occurs in clouds of droplets, and studying the evaporation of single liquid drops provides information on the evaporation characteristics of the fuel as a whole. Droplet evaporation tests on the chicken litter fuel were carried out using the suspended droplet/moving furnace technique. For some tests, a fine wire thermocouple was used as the droplet suspension in order to measure the distillation characteristics of the fuel. An existing computational model based on continuous ther- modynamics was used to model the evaporation of the fuel. The modelled composition of the fuel was based on an existing pyrolysis field ionization mass spectrometry (Py-FIMS) analysis and used five major groups of compounds. The properties for these groups re- quired for the model were determined using several prediction methods and the values then used in a numerical model. Model predictions of droplet temperatures calculated for the fuel showed good agree- ment with the measured temperatures, indicating that the modelled composition gave an accurate picture of the fuel. Droplet evaporation histories also agreed well with mea- surements, but were not capable of reproducing the observed disruption of the droplet produced by internal boiling at higher temperatures, nor the formation of a solid residue at the end of evaporation. Further enhancements to the model should allow the prediction of residue formation.Model predictions of droplet temperatures calculated for the fuel showed good agree- ment with the measured temperatures, indicating that the modelled composition gave an accurate picture of the fuel. Droplet evaporation histories also agreed well with mea- surements, but were not capable of reproducing the observed disruption of the droplet produced by internal boiling at higher temperatures, nor the formation of a solid residue at the end of evaporation. Further enhancements to the model should allow the prediction of residue formation.

Alternative fuels are becoming more important as fossil fuels become more expensive. This thesis describes the production and properties of a bio-oil produced from waste biomass, in this case chicken litter. A higher quality fuel was produced through thermal and chemical upgrading of the raw bio-oil; this fuel is similar in some respects to fossil fuels, as it has a high hydrocarbon content and energy density comparable to gasoline. Combustion of liquid fuels commonly occurs in clouds of droplets, and studying the evaporation of single liquid drops provides information on the evaporation characteristics of the fuel as a whole. Droplet evaporation tests on the chicken litter fuel were carried out using the suspended droplet/moving furnace technique. For some tests, a fine wire thermocouple was used as the droplet suspension in order to measure the distillation characteristics of the fuel. An existing computational model based on continuous ther- modynamics was used to model the evaporation of the fuel. The modelled composition of the fuel was based on an existing pyrolysis field ionization mass spectrometry (Py-FIMS) analysis and used five major groups of compounds. The properties for these groups re- quired for the model were determined using several prediction methods and the values then used in a numerical model. Model predictions of droplet temperatures calculated for the fuel showed good agree- ment with the measured temperatures, indicating that the modelled composition gave an accurate picture of the fuel. Droplet evaporation histories also agreed well with mea- surements, but were not capable of reproducing the observed disruption of the droplet produced by internal boiling at higher temperatures, nor the formation of a solid residue at the end of evaporation. Further enhancements to the model should allow the prediction of residue formation.Model predictions of droplet temperatures calculated for the fuel showed good agree- ment with the measured temperatures, indicating that the modelled composition gave an accurate picture of the fuel. Droplet evaporation histories also agreed well with mea- surements, but were not capable of reproducing the observed disruption of the droplet produced by internal boiling at higher temperatures, nor the formation of a solid residue at the end of evaporation. Further enhancements to the model should allow the prediction of residue formation.

The use of ultrasound contrast agents increases the information available for reconstruction during ultrasound imaging. Previously studied microbubbles, consisting of a gas core, are subject to limitations such as a short lifetime and a large size. Droplets with a liquid perfluorocarbon core that is stabilized by cellulose nanofibers eliminate these drawbacks, but require further investigation. By studying the frequency-dependent attenuation profile of the cellulose nanofiber coated perfluorocarbon droplets within an ultrasound field, information about the droplets as oscillators can be retrieved, enabling characterization of their physical properties. In this study, the frequency-dependent attenuation profile was experimentally acquired and compared between two concentrations, using flat transducers covering the frequency range of 1-15 MHz. The data collected in the time domain was processed and transformed into the frequency domain and the attenuation was calculated across the entire frequency range. Among the frequencies studied, the attenuation increases with frequency and covers the range of approximately 0.25-8.3 dB/cm and 0.01-3.3 dB/cm at the concentrations of 50 million droplets/ml and 10 million droplets/ml respectively. The attenuation reaches a minimum at 3 MHz within the highest concentration, compared to 4.43 MHz within the lowest. The increase of the attenuation with frequency is explained by the droplets not exhibiting large oscillations within the range covered. It is probable that the droplets do exhibit oscillations, due to a viscosity lower than that of water, but a resonance frequency is not found within the spectrum studied. This could be explained by a shell elasticity or a small droplet radius placing the resonance frequency outside of the spectrum studied, or high levels of damping broadening the resonance peak. Localizing the resonance frequency would enable characterization of these physical properties of the cellulose nanofiber shell as well as the perfluorocarbon liquid core of the droplets. The increase of the attenuation with frequency demonstrates that the droplets do not produce a maximized amount of scattering at a specific frequency within the range studied, which is observed among other oscillating particles implemented as ultrasound contrast agents. The attenuation is, however, larger than that of blood across all frequencies except for those among which the attenuation reaches its minimum. Potential errors that are affecting the results include droplet vaporization, the formation of flocs after the mechanical agitation has ceased, the experimental setup, the settings on the pulse generator, the sensitivity of the transducers and the processing code.

The Abraham solvation model (ABSM) is an experimentally derived predictive model used to help predict various solute properties. This work covers various uses for the ABSM including predicting molar enthalpies of vaporization, predicting solvent coefficients for two new solvents (2,2,5,5-tetramethyloxolane and diethyl carbonate), predicting values for multiple new ionic liquids (ILs). This work also introduces a novel method for updating IL ABSM parameters by updating cation- and anion-specific values using linear algebra and binary matrices.

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