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Download or read book Novel Aqueous Microgels and Their Applications written by Sepehr Mastour Tehrani and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the design, synthesis, and some new applications of aqueous microgels. One research objective was to prepare lanthanide-containing microgels which are resistant to lanthanide ion leaching in aqueous media and can be used in bead-based assays. I report the synthesis of lanthanide phosphate (LnPO4) nanocrystals embedded in poly(NIPAM/VCL/MAA) copolymer microgels. Here the microgels were first ion-exchanged with Ln3+ and then treated with PBS buffer to form LnPO4 crystals. The TEM images of the TbPO4-containing microgels in combination with SAXS studies show remarkable needle-like nanocrystals distributed throughout the microgel. Mass cytometry studies showed that these microgels resist ion leaching in different buffers. Another direction in my Ph.D. research was to design and synthesize temperature-invariant aqueous microgels that would preserve their dimensions and colloidal stability upon heating in water, and can serve as a host for enzymes in high-temperature reactions. For this purpose, I prepared poly(N-hydroxyethyl acrylamide) (PHEAA) microgels through a two-step synthesis. First, I prepared a precursor particle of poly[di(ethylene glycol) acrylate] in water, and then, these particles were subjected to aminolysis in dioxane with a mixture of ethanolamine and ethylenediamine to form to PHEAA-NH2 microgels. As a proof-of-concept study, I attached the enzyme horseradish peroxidase (HRP) to the microgels. Kinetic studies showed that immobilization led to improved enzyme stability at high temperatures compared to the native enzyme. I also examined the effect of the thermal response of microgels on the activity of enzymes. I prepared the thermo-responsive poly[oligo(ethylene glycol) methacrylate] (PEGMA) microgels and attached aminotetraethyleneglycol pendant groups to these microgels to act as a spacer and to make them biofunctionalizable. I found no discontinuous change in the activity of the immobilized enzyme as the microgel was heated through its VPTT. This study serves a guide for the biofunctionalization of protein repellent PEGMA microgels.