Papers by Keyword: Glycopolymer

Abstract: A novel end-functionalized glycopolymer poly (3-O-methacryloyl-D-glucofuranose) -b-poly (2-Diethylaminoethyl Methacrylate) (PMAGlc-b-PDEA-ZnTAPc) with zinc (II) teraamaninophthalocyanine was synthesized. First, a pH-responsive copolymer PMAIpG-b-PDEA was synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Then PMAIpG-b-PDEA reacted with ZnTAPc and deprotected to form a water-soluble and pH-responsive photosensitizer. The structure of the PMAGlc-b-PDEA-ZnTAPc was characterized by ¹H NMR and GPC. The photophysical properties were evaluated by UV-Vis and fluorescence spectra. The PMAGlc-b-PDEA-ZnTAPc can generate singlet oxygen species with good singlet oxygen quantum yields (Φ_△=0.38), which is believed to be the major cytotoxic reactive oxygen species (ROS) for photodynamic therapy. The ZnPc functionalized glycopolymer will be used as a potential photosensitizer in the fields of photodynamic therapy.

Abstract: Two pH-sensitive Glycopolymers with the same components but with different construction tailored biotin functionalities were developed for controlled release of bortezomib (BTZ).The initiator brominate biotin and glyco-monomer were synthesized precedently to produce the block-and random-biotinylated poly (2-Gluconamidoethyl methacrylate)-poly (2-Diethylaminoethyl methacrylate) (block/random Biotin-PGAMA-PDEA) via atom transfer radical polymerization (ATRP). The construction and composition of compounds and polymers were characterized by 1H NMR Spectroscopy. The block copolymer self-assembled into micelle according to the pH-response ability of the copolymer while the random one did not under certain conditions.

Abstract: A thermoresponsive glycopolymer poly-(N-isopropylacrylamide-co-6-O-vinylsebacoyl D-glucose) (poly-NIPAM-co-VSEG; PNE) has been prepared by free radical polymerization process, and subsequently processed into nanofibers with poly-L-lactide-co-ε-caprolactone (PLCL) using electrospinning. The thermoresponsive glycopolymer materials have been characterized by Fourier transform infrared (FTIR) spectroscopy, ¹H NMR, and scanning electron microscopy (SEM). And the lower critical solution temperature (LCST) of these thermoresponsive materials was also measured. The nanofibers containing PNE can greatly selective recognize with lectin Concanavalin A (Con A), and the adsorbed Con A can be easily eluted by 1 M glucose solution. These results indicate that PNE can separate and purify proteins, and also the temperature sensitive characteristic has the potential to achieve the intelligent control.

Abstract: Living radical polymerization of 3-O-methacryloyl-diaceton-D-glucose was carried out by the atom transfer radical polymerization (ATRP) method with an alkyl halide/copper-complex system. The effect of initiators, catalysts, ligand, and temperature on polymerization was studied in detail. Under the optimum condition, the time-conversion first-order plot was linear and the polydispersity of giycopolymer is relatively low, indicating that the polymerization is well controlled.

Abstract: Novel well-defined ABA-type triblock copolymers, (PMAIPGal-b-PLA-b-PMAIPGal), were synthesized by a three-step procedure: (a) melt polycondensation of L-lactic acid using stannous chloride (SnCl₂•2H₂O) as a catalyst, resulting in a hydroxyl-terminated prepolymer by alkyd condensation with 1,4-butanediol, followed by (b) esterification of the PLA hydroxyl end-groups with 2-bromoisobutyryl bromide, and (c) ATRP of 6-O-methacryloyl-1,2;3,4-di-O-isopropylidene-D-galactopyranose (MAIPGal) by the bromoisobutyryl initiating groups. The resultant copolymers were characterized by 1H NMR spectroscopy and gel permeation chromatography (GPC). The biocompatible and biodegradable copolymers have potential applications as tissue engineering biomaterials or controlled release drug delivery systems.

Abstract: Biocompatible and biodegradable synthetic materials have attracted considerable attention during the past two decades. In this work, a series of amphiphilic triblock copolymers containing D-galactopyranose were synthesized by atom transfer radical polymerization (ATRP). The macroinitiator was prepared by the esterification between poly(ethylene glycol) monomethyl ether with a number-average molecular weight of 1200 g/mol (MeOPEO-1200) and 2-bromoisobutyryl bromide. The sugar-bearing monomer, 6-O-methacryloyl-1,2;3,4-di-O-isopropylidene-D-galactopyranose (MAIPG) was polymerized using PMDETA/CuBr as catalytic system and anisol as solvent. The chemical structure and composition of the resultant polymer MeOPEO-b-PMAIPG were verified by 1H NMR. The molecular weights and their polydispersities were characterized by gel permeation chromatography (GPC). The results indicate that the polymerization follows the mechanism of ATRP. The amphiphilic copolymers can self-assembly to from micelles with PMAIPG as the core and PEO as the corona, which have potential applications as biomaterials or controlled release drug delivery systems.

Abstract: Glycopolymers carrying sulfate saccharides were found to suppress the formation of amyloid fibrils by amyloid beta peptides, as evaluated by fluorescence assay of thioflavin T and AFM. CD spectra showed that the conformation of amyloid beta peptides was changed from beta peptides depended on the glycopolymer additives, and that the glycopolymer additives reduced the β-sheet contents. Neutralization activity was confirmed by in vitro assay with HeLa cells. The sulfate group and the appropriate sugar contents were essential for the inhibitory effect.