Seeds are complex entities, within which the intricate processes of germination and early growth occur. We describe here a novel technique of our group in 2012 which is capable of simultaneous solution-, gel-, and solid-state analysis. CMP-NMR was applied to intact seeds where all components are studied and differentiated in situ. Characterization, germination and early growth of seeds were studied by variety of 1D and 2D 1H and 13C CMP-NMR experiments. Various metabolites, lipids, carbohydrate biopolymers and structural carbohydrates were first identified and further studied in germination and early growth stages. This research demonstrates the utility of CMP- NMR as a powerful tool to better understand the composition of seeds and processes underlying early seed growth.

The goal of this thesis was to test the applicability of biomarker analyses to better understand the glacial stratigraphic record of the Hudson Bay Lowlands and Oak Ridges Moraine. A biomarker analysis conducted on three geologic deposits from the Hudson Bay Lowlands showed that they can be differentiated based on organic matter (OM) inputs and stage of diagenesis, relating to paleoclimate and depositional environments. In the second study, a biomarker analysis was applied to samples from ten deposits in the Oak Ridges Moraine. These deposits were differentiated based on OM inputs relating to paleovegetation. Additionally, reincorporation and post-deposition alteration led to sample heterogeneity confirming the current understanding of glacial depositional processes and environments. This thesis shows that biomarker analyses can effectively differentiate and contextualize geologic deposits based on OM inputs and stage of diagenesis. This in turn will provide a more robust understanding of the stratigraphic record.

Irrigation using reclaimed wastewater can introduce organic contaminants and dissolved organic matter (DOM) to soils. Sorption of three common organic wastewater contaminants to five soils of diverse organic matter composition was studied both before and after the removal of soil carbohydrate and peptide components using acid hydrolysis. Results suggest that these polar components may block organic contaminants from accessing higher affinity sorption sites in soil organic matter. The sorptive fractionation of DOM by three mineral soils was studied to assess the terrestrial fate of this complex environmental matrix. Carboxyl- and aromatic-containing moieties appear to preferentially and reversibly sorb to mineral soils. Conversely, carbohydrate and peptide components of DOM preferentially remain in the aqueous phase while aliphatic moieties were selectively retained only by a soil with high surface area. This thesis illustrates that reclaimed wastewater should be applied to soils cautiously as it may degrade soil and groundwater quality.

Digital microfluidics (DMF) has recently emerged as a popular technology for a wide range of applications. In DMF, nL-mL droplets containing samples and reagents are controlled(i.e., moved, merged, mixed, and dispensed from reservoirs) by applying a series of electrical potentials to an array of electrodes coated with a hydrophobic insulator. DMF is distinct from microchannel-based fluidics as it allows for precise control over multiple reagent phases (liquid and solid) in heterogeneous systems with no need for complex networks of microvalves. In this thesis, digital microfluidics has been applied to address key challenges in the fields of chemistry, biology and medicine. For applications in chemistry, the first two-plate digital microfluidic platform for synchronized chemical synthesis is reported. The new method, which was applied to synthesizing peptide macrocycles, is fast and amenable to automation, and is convenient for parallel scale fluid handling in a straightforward manner. For applications in biology, I present the first DMF-based method for extraction of proteins (via precipitation) in serum and cell lysate. The performance of the new method was comparable to that of conventional techniques, with the advantages of automation and reduced analysis time. The results suggest great potential for digital microfluidics for proteomic biomarker discovery. Furthermore, I integrated DMF with microchannels for in-line biological sample processing and separations. Finally, for applications in medicine, I developed the first microfluidic method for sample clean-up and extraction of estrogen from one-microliter droplets of breast tissue homogenates, blood, and serum. The new method is fast and automated, and features >1000x reduction in sample use relative to conventional techniques. This method has significant potential for applications in endocrinology and breast cancer risk reduction. In addition, I describe a new microfluidic system incorporating a digital microfluidic platform for on-chip blood spotting and processing, and a microchannel emitter for direct analysis by mass spectrometry. The new method is fast, robust, precise, and is capable of quantifying analytes associated with common congenital disorders such as homocystinuria, phenylketonuria, and tyrosinemia.

Digital microfluidics (DMF) has recently emerged as a popular technology for a wide range of applications. In DMF, nL-mL droplets containing samples and reagents are controlled(i.e., moved, merged, mixed, and dispensed from reservoirs) by applying a series of electrical potentials to an array of electrodes coated with a hydrophobic insulator. DMF is distinct from microchannel-based fluidics as it allows for precise control over multiple reagent phases (liquid and solid) in heterogeneous systems with no need for complex networks of microvalves. In this thesis, digital microfluidics has been applied to address key challenges in the fields of chemistry, biology and medicine. For applications in chemistry, the first two-plate digital microfluidic platform for synchronized chemical synthesis is reported. The new method, which was applied to synthesizing peptide macrocycles, is fast and amenable to automation, and is convenient for parallel scale fluid handling in a straightforward manner. For applications in biology, I present the first DMF-based method for extraction of proteins (via precipitation) in serum and cell lysate. The performance of the new method was comparable to that of conventional techniques, with the advantages of automation and reduced analysis time. The results suggest great potential for digital microfluidics for proteomic biomarker discovery. Furthermore, I integrated DMF with microchannels for in-line biological sample processing and separations. Finally, for applications in medicine, I developed the first microfluidic method for sample clean-up and extraction of estrogen from one-microliter droplets of breast tissue homogenates, blood, and serum. The new method is fast and automated, and features >1000x reduction in sample use relative to conventional techniques. This method has significant potential for applications in endocrinology and breast cancer risk reduction. In addition, I describe a new microfluidic system incorporating a digital microfluidic platform for on-chip blood spotting and processing, and a microchannel emitter for direct analysis by mass spectrometry. The new method is fast, robust, precise, and is capable of quantifying analytes associated with common congenital disorders such as homocystinuria, phenylketonuria, and tyrosinemia.

The goal of this thesis was to test the applicability of biomarker analyses to better understand the glacial stratigraphic record of the Hudson Bay Lowlands and Oak Ridges Moraine. A biomarker analysis conducted on three geologic deposits from the Hudson Bay Lowlands showed that they can be differentiated based on organic matter (OM) inputs and stage of diagenesis, relating to paleoclimate and depositional environments. In the second study, a biomarker analysis was applied to samples from ten deposits in the Oak Ridges Moraine. These deposits were differentiated based on OM inputs relating to paleovegetation. Additionally, reincorporation and post-deposition alteration led to sample heterogeneity confirming the current understanding of glacial depositional processes and environments. This thesis shows that biomarker analyses can effectively differentiate and contextualize geologic deposits based on OM inputs and stage of diagenesis. This in turn will provide a more robust understanding of the stratigraphic record.

Irrigation using reclaimed wastewater can introduce organic contaminants and dissolved organic matter (DOM) to soils. Sorption of three common organic wastewater contaminants to five soils of diverse organic matter composition was studied both before and after the removal of soil carbohydrate and peptide components using acid hydrolysis. Results suggest that these polar components may block organic contaminants from accessing higher affinity sorption sites in soil organic matter. The sorptive fractionation of DOM by three mineral soils was studied to assess the terrestrial fate of this complex environmental matrix. Carboxyl- and aromatic-containing moieties appear to preferentially and reversibly sorb to mineral soils. Conversely, carbohydrate and peptide components of DOM preferentially remain in the aqueous phase while aliphatic moieties were selectively retained only by a soil with high surface area. This thesis illustrates that reclaimed wastewater should be applied to soils cautiously as it may degrade soil and groundwater quality.

This study describes two projects involving recent research on atmospheric ammonia. The first project investigates differences in modelling techniques of aerosol acidity using data from two recent field campaigns. Our results show that allowing or disallowing gas-particle partitioning in the Extended Aerosol Inorganic Model (E-AIM) changed the average modelled aerosol activity of H+ from one campaign by seven orders of magnitude and that disallowing gas-particle partitioning may not accurately represent the chemical state of the aerosols. The second project investigates the interference of reduced nitrogen in commercial chemiluminescent nitrogen oxide monitors with molybdenum oxide catalytic converters. This phenomenon is strongly dependent on the temperature of the catalytic converter. Our results show these instruments can have high conversion efficiencies of gaseous NH3 and NH4+ salts to NO at typical reported converter temperatures, but conversion efficiency varies between instruments and may be the result of uncertainty in reported converter temperature.

There is a growing need to develop rapid and cost-effective ecotoxicological tools for risk assessment because traditional methods examine endpoints such as mortality, which do not provide any insight into the mode of action (MOA) of the chemical. Research presented within this thesis illustrates the potential of 1H NMR-based metabolomics as a rapid and routine ecotoxicological tool that can elucidate a chemical’s MOA and also aid in the identification of metabolites of exposure. Metabolomics involves measuring the fluctuations in the endogenous metabolites of an organism within a cell, tissue, bio-fluid or whole organism in response to an external stressor. We focused on the model polycyclic aromatic hydrocarbon (PAH) phenanthrene, and the perfluoroalkyl acids (PFAAs) perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), due to their recalcitrant nature and widespread prevalence in soil environments. 1H NMR-based metabolomics analysis of the exposure of Eisenia fetida earthworms to sub-lethal phenanthrene exposure via filter paper contact tests revealed a concentration-dependent two-phased MOA: a linear correlation between the metabolic response and exposure concentration at low concentrations followed by a plateau in the responses at high concentrations. Alanine, glutamate, maltose, cholesterol and phosphatidylcholine emerged as potential indicators of phenanthrene exposure. An increased energy demand and an interruption in the conversion of succinate to fumarate in the Krebs cycle were observed due to phenanthrene exposure. Sub-lethal PFOA and PFOS exposure to E. fetida via contact tests for two days revealed heightened responses with higher PFOA and PFOS concentrations. Leucine, arginine, glutamate, maltose, and ATP were identified as potential indicators of PFOA or PFOS exposure. E. fetida responses were then investigated after exposure for two, seven and fourteen days to an artificial soil that was spiked with sub-lethal PFOS concentrations. An exposure time-dependent operation of two separate MOAs were identified. Both the contact tests and artificial soil exposure studies identified an elevation in fatty acid oxidation, a disruption in energy metabolism and biological membrane structure, and also an interruption of ATP synthesis following PFOA and PFOS exposure. This thesis illustrates the promise of NMR-based metabolomics as a routine tool for ecotoxicological assessment of contaminated sites.

This study describes two projects involving recent research on atmospheric ammonia. The first project investigates differences in modelling techniques of aerosol acidity using data from two recent field campaigns. Our results show that allowing or disallowing gas-particle partitioning in the Extended Aerosol Inorganic Model (E-AIM) changed the average modelled aerosol activity of H+ from one campaign by seven orders of magnitude and that disallowing gas-particle partitioning may not accurately represent the chemical state of the aerosols. The second project investigates the interference of reduced nitrogen in commercial chemiluminescent nitrogen oxide monitors with molybdenum oxide catalytic converters. This phenomenon is strongly dependent on the temperature of the catalytic converter. Our results show these instruments can have high conversion efficiencies of gaseous NH3 and NH4+ salts to NO at typical reported converter temperatures, but conversion efficiency varies between instruments and may be the result of uncertainty in reported converter temperature.