This thesis dealt with a novel fabrication of polymer brushes and lap-on-a-chip devices which were based on glycoconjugates with lectin binding ability. Glycopolymers are consisting of synthetic polymers with pendant saccharides. Their unique property such as sugar specific protein binding is well known. In general, the binding efficiency between the monomeric sugar and the sugar binding protein lectin is too weak to be detectable. However, the binding reaction can be significantly enhanced by multivalent presentation in the form of glycopolymers. Here, the glycopolymers have been prepared by "grafting from" method not only on solid substrates but also by controlled polymerization yielding diblock glycopolymers. Atom transfer radical polymerization (ATRP) was used for the fabrication of glycopolymers as well-controlled polymerization technique. Most reactions in this work were performed in moderate conditions such as room temperature and water as solvent. Several applications using glycopolymers were explored to manufacture practically useful "lab-on-a-chip" devices.In order to synthesize glycopolymer brushes, the glycomonomer 2-O-(N-acetyl--Dglucosamine) ethyl methacrylate (GlcNAcEMA) was synthesized by the modified König-Knorr reaction. Using this glycomonomer, a new multivalent glycopolymer platform for lectin recognition was fabricated. This new platform was manufactured by combining well-controlled ATRP reactions of glycomonomers with highly specific glycosylation reactions. The fabrication of multivalent glycopolymers consisting of poly(GlcNAcEMA) was succeeded by additional biocatalytic elongation of the glycans directly on the Silicon substrate. This sugar modification was carried out by specific glycosylation using recombinant glycosyltransferases. The bioactivity of the surface grafted glycans was investigated by fluorescence linked lectin assay (FLLA). Due to the multivalency of glycan ligands, the glycopolymer brushes showed very selective, specific and strong interactions with lectins. The multi-arrays of the glycopolymer brushes have shown a great potential for applications as screening devices of specific lectins.Recently, there is growing interest in surface gradient which contain gradually varied components along one or more given directions. We described two different forms of glycopolymer gradients. As first, a molecular gradient of the poly(2-hydroxyethyl methacrylate) (PHEMA) backbone of PGlcNAcEMA and an orthogonal pendant sugar gradient were prepared. The synthesis was conducted by dip-coating and biocatalytic elongation. The molecular gradient of glycopolymers was made by SI-ATRP from the silicon surface. The surface was characterized by the enzyme linked lectin assay technique and an AFM measurement. The binding intensity of lectin on the surface was proportional to the length of glycopolymer brushes. The glycan gradients have revealed a highly specific lectin binding ability. As second, an ATRP initiator gradient was prepared on the silicon surface and then the GlcNAcEMA polymerized from this initiator modified surface. The resulting Surface has shown different surface structures in comparison with the glycopolymer Gradient brushes. However, the fluorescence microscopic measurements have confirmed again this gradient surface possessed the specific lectin binding ability.As next, the wide applications of glycopolymer brushes were described in combination with electrochemical impedance spectroscopy (EIS) to realize an impedimetric glyco-biosensor (IGB). The GlcNAcEMA was polymerized directly from gold electrodes of EIS chips by SI-ATRP. Then, the fabricated IGB was analyzed by common surface characterization methods as well as EIS technique. The resulting surface has shown very sensitive and reproducible results. The combination of chemical polymer synthesis with electrochemical devices led to a successful fabrication of a novel glycopolymer platform with Protein selective surfaces. In addition to impedance measurement based IGB, a plasmonic flowthrough glyco-biosensor (PFGB) and real-time polymerization monitoring device using surface acoustic wave (SAW) were described in detail. PFGB possesses a strong benefit by using an inexpensive polycarbonate membrane, while SAW measures the mass viscosityand the conductivity with high sensitivity. In usual, these three techniques were driven by microfluidic systems. Therefore, they have unique advantages such as handling of small sample sizes, saving reagents, the enhanced efficiency of the assays, and the reduction of cross-contamination. In particular, IGB and PFGB have revealed their ability as alternative biosensors to commercially available SPR. Thus, the microfluidic glycopolymer biosensors are potentially usable for new simplified diagnostic tools to detect cancer-related lectins in blood serum.Glycopolymers have been also applied for the synthesis of core-shell microspheres. As first, silica particles were used as solid substrate. After initiator modification, GlcNAcEMA was polymerized. As a result, the particles showed core-shell structures, but large Agglomeration of particles was observed which might be caused from inter-particle coupling. As second, the glycomonomer GlcNAcEMA was polymerized using PHEMA as the macroinitiator. The resulting diblock glycopolymer PHEMA-b-PGlcNAcEMA was investigated by microscopic methods, DLS and FCS measurements. PHEMA is a well known polymer characterized by its water-swellable property. However, PHEMA cannot be fully dissolved in water because of its hydrophilic functional groups. Although the glycopolymer PGlc-NAcEMA is distinguished only by the sugar pendants from PHEMA, the produced diblock glycopolymers revealed core-shell microsphere formation. This result indicates that the sugar pendants of the glycopolymers have much higher hydrophilicity in comparison with PHEMA. The diverse microscopic observations have presented with the micelle structure of the PHEMA-b-PGlcNAcEMA diblock copolymer. The size of the particles was estimated around 32 nm in diameter and it agreed quite well with the results of DLS and FCS measurements. The lectin binding property of these polymers was also demonstrated bymicroscopic and FCS measurement.In conclusion, the synthesized GlcNAcEMA has shown high potential applications for the fabrication of diverse glycochips and glyco-particles. The prepared glycopolymers including brushes and micelles possessed a specific lectin binding property. The introduced novel platforms are expected to be used in many fields of chemistry, biology, diagnostics, and biomedicine as powerful synthetic materials.
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