Co-polymers of 2-(2-methoxyethoxy)ethyl methacrylate (MEO 2 MA) and oligo(ethylene glycol) methyl ether methacrylate (OEGMA 300 , M n = 300 g/mol) of various composition were synthesized at 60 • C in ethanol solution either by conventional radical polymerization (RP) or atom transfer radical polymerization (ATRP). Both techniques led to co-polymers P(MEO 2 MA-co-OEGMA 300 ) in high yields. However, ATRP provided better defined co-polymers with controlled molecular weight, composition and molecular weight distribution. Nevertheless, all the samples exhibited a lower critical solution temperature (LCST) in aqueous medium (i.e., pure deionized water or physiological buffer). Sharp and reversible phase transitions were observed in all cases by turbidimetry and dynamic light scattering. This thermoresponsive behavior was demonstrated to be directly linked to the MEO 2 MA/OEGMA 300 composition of the formed co-polymers. Thus, the LCST of the co-polymers could be precisely adjusted in the temperature range 28-65 • C. © Koninklijke Brill NV, Leiden, 2009

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Glycans carry a vast range of functions in nature. Utilizing their properties and functions in form of polymers, coatings or glycan derivatives for various applications makes the synthesis of modified glycans crucial. Since amines are easy to modify for subsequent reactions, we investigated regioselective amination conditions of different saccharides. Amination reactions were performed according to Kochetkov and Likhoshertov and accelerated by microwave irradiation. We optimized the synthesis of glycosylamines for N-acetyl-d-galactosamine, d-lactose, d-glucuronic acid and l-(−)-fucose using the design of experiments (DoE) approach. DoE enables efficient optimization with limited number of experimental data. A DoE software generated a set of experiments where reaction temperature, concentration of carbohydrate, nature of aminating agent and solvent were investigated. We found that the synthesis of glycosylamines significantly depends on the nature of the carbohydrate and on the reaction temperature. There is strong indication that high temperatures are favored for the amination reaction.

The base pairing property and the “melting” behavior of oligonucleotides can take advantage to develop new smart thermoresponsive and programmable materials.