Stimuli responsive polymers (SRP) have attracted a lot of attention, due to their potential and promising applications in many fields, as protein-ligand recognition, on-off switches for modulated drug delivery or artificial organs. Poly(N-isopropylacrylamide) (PNIPAM) is one of the most widely studied polymers due to its lower critical solution temperature (LCST) at ~ 32° C in aqueous solution. Additionally, glycopolymers, where free sugar units are present, have potentially interesting applications especially in bio-recognition where sugars play an important role. In this work, our interest was focused on the synthesis of glycomonomers and its block- and random- copolymers with NIPAM. NIPAM homopolymers with an active chain transfer unit at the chain end could be prepared by RAFT. They were used as macro-chain transfer agents to prepare a variety of sugar containing responsive block copolymers from new glycomonomers by the monomer addition concept. The LCSTs of the aqueous solutions of the copolymers are affected strongly by the comonomer content, spacer chain length of the glycomonomer and the chain architecture of the copolymers. These polymers were coated on a solid substrate by spin coating and crosslinked by plasma immobilization. Characterization of the polymers was performed by nuclear magnetic resonance spectroscopy (NMR), ultraviolet (UV), dynamic light scattering (DLS, detection of aggregation behaviour) and gel permeation chromatography (GPC). Polymer films were investigated by ellipsometry, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) regarding their surface properties. Afterwards sulfation of sugar – OH groups was performed in order to obtain heparin like structure, as heparin exhibits numerous important biological activities, like good interaction with diverse proteins. Finally, affinity of the polymers (sulfated and non sulfated form) on a solid support to the endothelial cells was investigated.
| Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa:de:qucosa:23965 |
| Date | 05 September 2007 |
| Creators | Özyürek, Zeynep |
| Contributors | Voit, Brigitte, Müller, Axel H. E., Adler, Hans-Jürgen |
| Publisher | Technische Universität Dresden |
| Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
| Language | English |
| Detected Language | English |
| Type | doc-type:doctoralThesis, info:eu-repo/semantics/doctoralThesis, doc-type:Text |
| Rights | info:eu-repo/semantics/openAccess |
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