Investigations of Polymer Conformation and Colliod Stability

聚合物表面涂层强烈影响胶体稳定性， 广泛的重要工程过程。 聚合物 在水和废水中用作絮凝剂或稳定剂 水处理，选矿，水煤浆 稳定化，油漆生产，食品胶体稳定化， 分离菌悬液，造纸，酿造， 陶瓷制造，药物制备，以及 农业化学制剂 稳定性、流动性和 天然存在的胶体颗粒的化学反应性 在地下水和其他水生系统中， 由有机分子的表面涂层控制。 以来 这些颗粒会影响化学物质或 放射性污染物和病原体的生存 微生物，有机涂层胶体的存在必须 在预测危险物质命运的模型中得到解释， 环境中的废物。 本研究旨在阐明 表面吸附聚合物影响胶体稳定性 水系统 理论和实验研究 表明包覆胶体颗粒的稳定性 关键取决于吸附的构象 分子。 尽管聚合物的重要性不言而喻 构象对胶体稳定性的影响，没有实验 直接测量吸附的构象的技术 聚合物 这项研究的一个主要目标是开发一种 一种检测单链DNA构象的方法 分子吸附到胶态胶乳颗粒使用 这就是所谓的“DNA足迹”。 这项技术， 最初由生物化学家开发，用于研究蛋白质/DNA 相互作用，将被用来确定的分数， 吸附的DNA分布在列车，环和 尾 这种分布对 将研究表面和溶液化学， 与胶体稳定性的伴随变化有关。

Polymer surface coatings strongly affect colloid stability in a broad spectrum of important engineering processes. Polymers are used as flocculants or stabilizers in water and waste treatment, mineral processing, coal-water slurry stabilization, paint production, food colloid stabilization, separation of bacterial suspensions, paper making, brewing, ceramics fabrication, pharmaceutical preparation, and agrochemical formulation. The stability, mobility, and chemical reactively of colloidal particles naturally present in groundwater and other aquatic systems are strongly controlled by surface coatings of organic molecules. Since these particles influence the transport of chemical or radioactive contaminants and the survival of pathogenic microorganisms, the presence of organic-coated colloids must be accounted for in models that predict the fate of hazardous wastes in the environment. This research seeks to clarify the mechanisms by which surface-adsorbed polymers influences colloid stability in aqueous systems. Theoretical and experimental studies indicates that the stability of coated colloidal particles depends critically on the conformation of the adsorbing molecule. Despite the implied importance of polymer conformation on colloid stability, there are no experimental techniques which directly measure the conformation of adsorbed polymers. A major goal of this research is to develop a method for examining the conformation of single-stranded DNA molecules adsorbed to colloidal latex particles using a technology called "DNA footprinting". This technology, originally developed by biochemists to investigate protein/DNA interactions, will be used to ascertain the fraction of adsorbed DNA that is distributed between trains, loops and tails. The response of this distribution to changes in surface and solution chemistry will be investigated and related to concomitant changes in colloid stability.