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Preterm birth is a global health challenge and the leading cause of neonatal mortality. Each year, about 15 million babies are born preterm globally. Traditional tools that have been exploited for the detection of preterm birth biomarkers are expensive, time consuming, or lack multiplexing capabilities. The work described in this dissertation highlights techniques developed to detect preterm birth biomarkers rapidly and accurately in the effort to mitigate preterm birth risk. In this dissertation, I first demonstrated the use of stereolithography digital light processing-based 3D printing and microfluidics for the development of microfluidic devices that had microvalves for fluid control. I then used these devices for microchip electrophoresis and fluorescence detection of five preterm birth biomarkers from a published panel. Next, I presented developments in 3D printed microchip electrophoresis device design. I separated amino acids and preterm birth biomarkers in a serpentine device design, obtaining good resolution, separation efficiency, and improved preterm birth biomarker peak capacity. Finally, I demonstrated the integration of solid-phase extraction with microchip electrophoresis in 3D printed microfluidic devices. These integrated devices enabled a seamless transition from preterm birth biomarker enrichment and labeling to microchip electrophoresis separation and fluorescence detection. The work described in this dissertation shows promise in advancing key tools needed to address preterm birth risk rapidly and effectively.

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As sessile organisms, plants manage stress through complex signaling networks involving phytohormones such as phytosulfokine (PSK). PSK, a disulfated pentapeptide, regulates plant growth, development, and stress responses by interacting with specific PSK receptors (PSKRs). In this study, we explored the trafficking dynamics of PSK, its post-application fate, and the synthesis of an analog. We administered both native PSK and a fluorescent version tagged with TAMRA (5(6)-carboxytetramethylrhodamine) to various Arabidopsis thaliana genotypes, including wild type, a PSKR-deficient mutant, and a strain overexpressing PSKR1 tagged with green fluorescent protein (GFP) over the wild-type background. Fiber-optic fluorescence microscopy revealed that receptor presence influences PSK’s internal movement. Additionally, we extracted TAMRA–PSK from treated plants and recovered it using solid-phase extraction to assess its stability post-application. HPLC analysis suggested that TAMRA–PSK is substantially unchanged in the plant matrix. Furthermore, a PSK analog was partially synthesized via solid-phase peptide synthesis for future studies.

BACKGROUND:The widespread utilization of organic compounds in modern society and their dispersion through wastewater have resulted in extensive contamination of source and drinking waters. The vast majority of these compounds are not regulated in wastewater outfalls or in drinking water while trace amounts of certain compounds can impact aquatic wildlife. Hence it is prudent to monitor these contaminants in water sources until sufficient toxicological data relevant to humans becomes available. A method was developed for the analysis of 36 trace organic contaminants (TOrCs) including pharmaceuticals, pesticides, steroid hormones (androgens, progestins, and glucocorticoids), personal care products and polyfluorinated compounds (PFCs) using a single solid phase extraction (SPE) technique with ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method was applied to a variety of water matrices to demonstrate method performance and reliability.RESULTS:UHPLC-MS/MS in both positive and negative electrospray ionization (ESI) modes was employed to achieve optimum sensitivity while reducing sample analysis time (<20min) compared with previously published methods. The detection limits for most compounds was lower than 1.0 picogram on the column while reporting limits in water ranged from 0.1 to 15ng/L based on the extraction of a 1L sample and concentration to 1mL. Recoveries in ultrapure water for most compounds were between 90-110%, while recoveries in surface water and wastewater were in the range of 39-121% and 38-141% respectively. The analytical method was successfully applied to analyze samples across several different water matrices including wastewater, groundwater, surface water and drinking water at different stages of the treatment. Among several compounds detected in wastewater, sucralose and TCPP showed the highest concentrations.CONCLUSION:The proposed method is sensitive, rapid and robust / hence it can be used to analyze a large variety of trace organic compounds in different water matrixes.

The behaviour and impact of pharmaceuticals in the environment are still poorly understood. Pharmaceuticals are widely used and continually released into the environment causing increasing concerns about their impact on the environment beyond the intended human or veterinary use. Prescribed pharmaceuticals, typically, enter the environment either through excretion after human use or disposal of surplus medication. Sewage treatment plants do not completely remove pharmaceuticals and their metabolites and these have been detected in sewage treatment plant effluent and receiving waters. Land application of treated sewage effluent is widely practiced in New Zealand as an alternative to surface water discharge. Methods were developed to determine selected pharmaceuticals in environmental matrices such as sewage effluent, sewage solids, soil, and soil water. From these, pharmaceutical removal efficiencies were determined for three common sewage treatment processes; activated sludge, composting and land application of sewage effluent. The impacts of some common pharmaceuticals on soil microbial communities, together with the effect of prolonged exposure to sewage effluent on these communities were examined. Additionally, toxicity of sewage effluent, and toxicity mechanisms of specific pharmaceuticals were investigated using luminescent micro-organisms and lettuce seedlings. Pharmaceuticals were successfully detected in sewage effluent, sewage solids, compost, soil and soil water. The sewage treatment processes investigated, including land application, were able to remove or reduce pharmaceutical concentrations in sewage. In case of land application, volcanic soils were more efficient than sandy soils in pharmaceutical removal while irrigation rate and level of sewage pre-treatment also showed some effect on removal efficiency. Pharmaceuticals were not acutely toxic at environmental levels currently detected. Exposure of microbial communities to unnaturally high levels of pharmaceuticals did demonstrate that most pharmaceuticals were potentially able to induce stress in the microbial community although microbes were able to metabolise some of these pharmaceuticals. Twelve years of effluent irrigation resulted in microbial adaptation to aspirin, acetaminophen and tetracycline, indicating that these pharmaceuticals had an effect on microbial community. Presently, land application of treated sewage waste may be a suitable treatment for additional pharmaceutical removal provided that land application schemes are designed appropriately, and pharmaceutical accumulation in the soil is occasionally monitored. It would be prudent to recognise the potential risk that could be caused by chronic exposure to pharmaceuticals such that continued vigilance may lead to future indications of chronic effects at an early stage.

Antimony film electrode was studied for the use in a voltammetric analysis of organic compounds. The substance chosen as an analyte was trifluralin, which is used as a pesticide. The comparison of different substrate electrodes was carried out between five electrodes, which were gold, silver, copper, polished amalgam and glassy carbon electrode (GCE). Best performance was observed on antimony film glassy carbon electrode (SbFGCE). It provided higher sensitivity and lower limit of quantification in comparison with bare GCE. The antimony film was stable and it provided good reproducibility (RSD = 5.2 %). Parameters of an electrochemical preparation of SbFGCE were optimized. Conditions for determination of concentration of trifluralin were optimized on newly prepared SbFGCE. The best conditions were in a solution of methanol and 0.1 M hydrochloric acid in 1:1 ratio measured by differential pulse voltammetry. The limit of quantification was determined as 1.2·10-6 mol·l-1 . A direct voltammetric measurement on SbFGCE was carried out in a model river sample. Lower limits of quantification were achieved with solid phase extraction (SPE). Recovery values were 86 ± 8 % in deionized water with a preconcentration factor of 125. The limit of quantification was lowered to value 1.1·10-8 mol·l-1 . The extraction...

Les antibiotiques sont des polluants présents dans les écosystèmes aquatiques, réceptacles ultimes des substances anthropiques. L’étude de ces composés porte sur leur rémanence dans le milieu ou leurs effets sur des organismes naturels. De nombreux efforts ont été faits à l’échelle mondiale pour l’évaluation de la qualité environnementale des différentes ressources en eau pour la survie des espèces aquatiques mais aussi pour la consommation humaine et le risque sanitaire lié. Dans ce but, l’optimisation des techniques analytiques pour ces composés dans les systèmes aquatiques demeure une nécessité. Notre objectif est de développer des méthodes d’extraction et de détection pour 12 molécules appartenant à la famille des aminoglycosides et de la colistine dans les eaux des stations d’épuration et les eaux hospitalières. L’absence des méthodes d’analyse pour ces composés ainsi que le manque des études permettant leur détection dans l’eau sont les raisons de leur étude. L’Extraction sur Phase Solide (SPE) en mode classique (hors ligne) ou en ligne, suivie d’une analyse par la Chromatographie Liquide couplée à la Spectrométrie de Masse (LC/MS/MS) est la méthode la plus couramment employée pour ce type d’analyse. Les paramètres sont optimisés et validés afin d’assurer les meilleures conditions utilisées dans les analyses environnementales. Cette technique a été appliquée sur des échantillons réels des eaux des stations d’épuration à Bordeaux et au Liban. / Antibiotics are pollutants present in aquatic ecosystems ultimate receptacles of anthropogenic substances. These compounds are studied as their persistence in the environment or their effects on natural organisms. Numerous efforts have been made worldwide to assess the environmental quality of different water resources for the survival of aquatic species, but also for human consumption and health risk related. Towards goal, the optimization of analytical techniques for these compounds in aquatic systems remains a necessity. Our objective is to develop extraction and detection methods for 12 molecules of aminoglycosides and colistin in sewage treatment plants and hospitals waters. The lack of analytical methods for analysis of these compounds and the deficiency of studies for their detection in water is the reason for their study. Solid Phase Extraction (SPE) in classic mode (offline) or online followed by Liquid Chromatography analysis coupled with Mass Spectrometry (LC/MS/ MS) is the most method commonly used for this type of analysis. The parameters are optimized and validated to ensure the best conditions for the environmental analysis. This technique was applied to real samples of wastewater treatment plants in Bordeaux and Lebanon.

Este estudo apresenta o desenvolvimento da metodologia de extração em fase sólida e separação em cromatográfica líquida acoplada a espectrometria de massas em sequencia, SPE-LC-MS/MS, para a determinação de 21 (vinte e um) fármacos pertencentes a diferentes classes terapeuticas, 1 (uma) droga de abuso e seu principal metabólito, em amostras de água superficial. A separação cromatográfica foi otimizada estudando o desempenho de fases estacionárias e fases móvies. A quantificação dos compostos selecionados foi realizada com a ionização por eletronebulização (electrospray ionization- ESI) e o espectrômetro de massas operando no modo de Monitoramento de Múltiplas Reações (Multiplas Reaction Monitoring- MRM). A validação da metodologia proposta foi realizada utilizando os parâmetros de seletividade, efeito de matriz, faixa de trabalho, linearidade, limites de detecção (LD) e quantificação (LQ), precisão, exatidão, recuperação e robustez. A validação da metodologia permitiu a sua aplicação na avaliação da distribuição dos 23 compostos selecionados, nas águas da represa Guarapiranga, um dos principais sistemas produtor de água potável da Região Metropolitana de São Paulo (RMSP). A presença desses poluentes nos ambientes aquáticos é proveniente da liberação direta do esgoto urbano das habitações do seu entorno, como consequência do precário sistema de saneamento básico. As águas da represa Guarapiranga foram avaliadas em 14 (quatorze) locais estrategicamente escolhidos e amostradas durante 3 (três) campanhas de coleta de amostra (agosto de 2011, setembro de 2012 e abril de 2013). Nessas amostras foram quantificados acetaminofeno (9,6 - 254 ng L-1), atenolol (8,5 177 ng L-1), benzoilegonina (7,9 139 ng L-1), cafeína (27 27386 ng L-1), carbamazepina (12 358 ng L-1), clortalidona (9,4 35 ng L-1), cocaína (12,8 2650 ng L-1), diclofenaco (8 35 ng L-1), enalapril (20 ng L-1), losartana (6,7 114 ng L-1) e valsartana (9,7 - 47 ng L-1). O ponto de coleta denominado de GU103-12 (23°4188.5S 46°4467.3W) foi a região que apresentou os valores mais elevados quanto ao nível de concentração dos compostos avaliados e ao índice de risco integrado de poluição química aquática (Integrated Risk Index of Chemical Aquatic Pollution IRICAP). O estudo também foi realizado em amostras de água de reservatórios das Unidades de Gerenciamento de Recursos Hídricos (UGRHI) 5 e 6 do Estado de São Paulo. Os resultados demonstraram que o uso e a ocupação do solo influenciam diretamente na qualidade da água dos reservatórios, evidenciando a necessidade de implementar melhorias no sistema de coleta de esgoto e de ocupação irregular para evitar a contaminação e o descarte inadequado em ambientes aquáticos. / This study presents the development of the methodology of solid phase extraction and liquid chromatography - tandem mass spectrometry, SPE-LC-MS/MS, for the determination of 21 (twenty one) pharmaceuticals belonging to different therapeutic groups, 1 (one) illicit drug and its major metabolite, in surface water samples. The chromatographic separation was optimized by studying the performance of different stationary and mobile phases. Quantitation of selected compounds was performed by electrospray ionization (ESI) and the mass spectrometer operating in a multiple reaction monitoring (MRM) mode. The validation of the proposed methodology was performed using the parameters of selectivity, matrix effect, dynamic range, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, recovery and robustness. The validation of methodology allowed to apply the methodology in the evaluation of the distribution of the 23 (twenty one) selected compounds, in Guarapiranga Dam waters, an of the major producer system of drinking water of the Metropolitan Region of São Paulo (MRSP). The presence of these pollutants in aquatic environments is from the direct release of urban sewage from the homes of your surroundings, as a result of poor sanitation system. The waters of Guarapiranga dam were evaluated in 14 (fourteen) locations strategically chosen and sampled in 3 (three) campaigns of sample collection (August 2011, September 2012 and April 2013). In these samples were quantified acetaminophen (9.6 - 254 ng L-1), atenolol (8.5 - 177 ng L-1), benzoylegonine (7.9 - 139 ng L-1), caffeine (27 - 27386 ng L-1) carbamazepine (12 - 358 ng L-1), chlorthalidone (9.4 - 35 ng L-1), cocaine (12.8 - 2560 ng L-1), diclofenac (8 - 36 ng L-1), enalapril (20 ng L-1), losartan (6.7 - 114 ng L-1) and valsartan (9.7 - 47 ng L-1). The sample siting GU103-12 (23°4188.5S 46°4467.3W) was the region with the highest values in the level of concentration of the target compounds and the integrated risk index of chemical aquatic pollution (IRICAP). The study was also conducted on water samples from reservoirs of the UGRHI (Unit of Water Resources Management) 5 and 6, State o São Paulo. The results showed that the use and occupation of land directly influence the reservoir water quality highlighting the need to implement improvements in sewage collection system and illegal occupation to prevent contamination and the improper disposal in aquatic environments.