Changes in the ionic and dipolar molecular mobility in a polymer system are the basis for the changes in the dielectric mechanical properties of polymer materials. Frequency Dependent Dielectric Measurements (FDEMS) and Ion Time-of-Flight (ITOF) are two important techniques to investigate ionic and dipolar molecular mobility in polymer systems. The results can be related to the macro- and molecular dielectric, electrical and dynamic properties of polymeric materials. The combination of these two methods provides a full view of electric, dielectric and dynamic behavior for the systems as they undergo chemical and/or physical changes during polymerization crystallization, vitrification, and/or phase separation.;The research on microscopic mass mobility in polymer systems was done on three aspects: (1) ion mobility in an epoxy-amine reaction system; (2) dipolar mobility and relaxation during dimethacrylate resin cure and (3) dye molecule migration and diffusion in polymer films.;In the ion mobility study, we separately monitor the changes in the ion mobility and the number of charge carriers during the epoxy-amine polymerization with FDEMS and ITOF measurements. The isolation of the number of carriers and their mobility allows significant improvement in monitoring changes in the state and structure of a material as it cures.;For the dipolar mobility and relaxation study, FDEMS measurements were used to detect structural evolution and spatial heterogeneity formation during the polymerization process of dimethacrylate resins. The dielectric spectra, glass transition (Tg) profiles and dynamic mechanical measurements were used to investigate the existence of two cooperative regions of sufficient size to create two alpha-relaxation processes representing oligomer rich and polymer microgel regions during the polymerization.;For the dye migration research, we tried to develop a visually color changing paper (VCP) due to dye molecule migration in polymer films. The mobility of dye molecules in polyvinyl films was controlled by the acidity of the environment. Ionamine derivatives of dyes were stable when mixed with acid. their diffusion in polymer films can be quickly triggered as the result of an acid/base neutralization reaction. The effect of the type of base, acid and the compatibility of polymer films on the diffusion rate is discussed.

Two manifolds were designed to determine phosphate concentrations. The linear range for the 2-channel manifold was 0 to 30 mg L-1, and that for the 3-channel manifold was 0 to 400 mg L-1. Optimized conditions for the determination of arsenic with molybdenum-blue method were 0.5% w/v ascorbic acid, 0.4 M sulfuric acid in the molybdate solution and 80°C reaction temperature. A method for determination of arsenic using pervaporation flow injection hydride generation with visible spectrophotometry was developed. The method was sensitive for low arsenic concentrations (≤ 10 μg L-1), with sensitivity decreasing as arsenic concentration increased. There was no heating required, and the pervaporation membrane transferred only arsine. The analytical performance of two arsenic test kits was assessed. The Alpha Environmental kit cannot be recommended for arsenic measurement in water. The Hach kit was reliable for measuring arsenic concentrations greater than 70 μg L-1. A modified reaction tube was constructed that allowed NaBH4 solution to be delivered into the reaction mixture to replace zinc powder in the Hach kit, with no loss of gases. A more quantitative way of measuring arsenic using the Hach kit was developed by measuring the B-value of the color of jpeg images of test strips taken by a desktop scanner. Leersia oryzoides grown in soil amended with 110 mg kg-1arsenic extracted up to 305 μg g-1 and 272 μg g-1 arsenic into its shoots and roots respectively, giving a shoot:root quotient (SRQ) of 1.12 and phytoextraction coefficients (PEC) up to 1.3 in greenhouse experiments. Five supervised arsenic-related projects were reported. All except one of these reports fell short of the standards acceptable for a publishable manuscript. Factors such as high expectations, competitive entrance requirements and good motivation were responsible for the publishable report. For the remaining reports, problems with working in a team, relatively low expectations and lack of motivation were responsible. A laboratory-based research subject was successfully investigated in middle school classrooms. The program had been run for four consecutive years. Collaboration with the classroom teacher ensured that the program agreed with the school curriculum. All participants recommended continuation of this program.

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<p>Cell-derived extracellular vesicles (EVs) are increasingly being recognized as an important mediator of intercellular communication, immune response and waste disposal. Due to the prevalent dissemination in most biofluids, EVs provide a promising alternative for non-invasive liquid biopsy in clinics. With internal cargoes well-preserved by EV membranes, EV-containing DNA, RNA, proteins, lipids and metabolites are widely investigated for biomarker discovery and disease progression and therapeutics monitoring. Among them, proteins and their post-translational modifications (PTMs), are the direct phenotypic indicators of pathophysiological states. Besides, development of liquid chromatography-tandem mass spectrometry (LC-MS/MS) has allowed high-throughput and discovery-driven bioanalysis on proteomics, including EV proteomics. Nevertheless, the translational research and clinical applications on EVs are severely hampered due to the lack of suitable and efficient isolation methods as well as robust and sensitive proteomic approaches. This dissertation proposes EV proteomic strategies for therapeutic surveillance by using a novel EV isolation technique. Chapter One introduces overall status of proteomics and phosphoproteomics in translational and clinical analysis for to-date medical sciences. Chapter Two highlights a novel EV isolation method termed EV total recovery and purification (EVtrap). Chapter Three delves into the development of a pipeline proteomic strategy that utilizes EV P450 enzymes to monitor drug metabolic behaviors. Finally, Chapter Four explores the possibility of leveraging protein PTMs in EVs, especially tyrosine phosphorylation, to indicate drug therapeutic efficacy in a clinical setting. This dissertation primarily proposes EV-based liquid biopsy for revolutionary clinical analysis, especially on longitudinal monitoring for <em>in vivo</em> treatment response.</p>

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Studies of the electrophoretic transport of charged macromolecules have been performed to elucidate the molecular mechanisms involved in gel electrophoresis and to discriminate among various theories which attempt to describe chain motion in gels. Experiments with high molecular weight, synthetic polyelectrolytes establish gel electrophoresis as a viable technique for characterizing polymers according to chain length distribution. Mobility has been measured as a function of degree of polymerization, electric field strength, gel concentration, ionic strength, chain topology, and charge density. Trends for synthetic polyelectrolytes, principally poly(styrenesulfonate), qualitatively match those observed for DNA. By comparison of the electrophoretic mobility of polyions in the absence and presence of a gel, the importance of interactions between polymer and gel fibers is demonstrated. High resolution separations which occur in the presence of a gel are a result of interactions of between the polyion and gel fibers. The frequency of such interactions is influenced by the size of the polymer chain relative to the mesh spacing in the gel matrix. Entanglement of the polymer in the matrix plays a fundamental role in the separation process. Variations in mobility among chains with different topologies (linear, star-branched, and circular molecules) provide strong evidence for the recently proposed "entropic barriers" transport theory for weakly entangled chains. For highly entangled linear polymers, theories based on reptation appear to predict the proper scaling dependence of mobility on chain length at low electric field strengths.

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