Poly-dl-lactide-poly(ethylene glycol) (PELA) triblock copolymers were synthesized with lanthanum acetate as the initiator. PELA microspheres with entrapped Vibrio Cholera antigen and outer membrane protein (OMP) were ...Poly-dl-lactide-poly(ethylene glycol) (PELA) triblock copolymers were synthesized with lanthanum acetate as the initiator. PELA microspheres with entrapped Vibrio Cholera antigen and outer membrane protein (OMP) were prepared by a double emulsion W/O/W based on solvent extraction methods. The obtained microspheres showed smooth and spherical surface and their size varied between 0.5 and 5.0 mu m, which are suitable for oral targeting delivery system. The distribution tests in rabbits and mice through scanning electronic micrography and fluorescence microscope indicated that microspheres have successfully reached the immunization-related tissues, such as the liver, spleen and intestinal peyer's patches, following oral administration. The PELA microspheres were also evaluated as an efficient antigen delivery system by enhancing a higher protective ratio against live Vibrios Cholera.展开更多
In order to expand the application of poly（p-dioxanone） or PPDO in biomedical area,a series of novel copolymers were synthesized successfully by one-step,melted copolymerization of p-dioxanone（PDO） and L-phenylala...In order to expand the application of poly（p-dioxanone） or PPDO in biomedical area,a series of novel copolymers were synthesized successfully by one-step,melted copolymerization of p-dioxanone（PDO） and L-phenylalanine N-carboxyanhydride（L-Phe-NCA） monomers.With the in-feed molar ratio of L-PheNCA /PDO equal to 1/20,the conversions of the two kinds of monomers were calculated from 1H NMR. The average molecular weight and polydispersity of the copolymer increase with the increasing reaction time and catalyst concentration.However,the conversions of the two kinds of monomers did not change with the reaction conditions.A three-step mechanism is presented and proved by high resolution 1H NMR and IR spectrums.展开更多
In order to exploit the biological functions of materials, a series of new random terpolymers were synthesized by the ring-opening polymerization of p-dioxanone, trimethylene carbonate, and L-phenylalanine N-carboxyan...In order to exploit the biological functions of materials, a series of new random terpolymers were synthesized by the ring-opening polymerization of p-dioxanone, trimethylene carbonate, and L-phenylalanine N-carboxyanhydride（L-PheNCA） in the presence of stannous octoate. The terpolymers were characterized by 1H-NMR, 13C-NMR, FTIR, and gel permeation chromatography. The effects of the reactant ratio, catalyst dosage, reaction temperature and time on the copolymerization were investigated, and were found to regulate the composition of the terpolymer. Increases in the reaction temperature, polymerization time, L-Phe-NCA monomer amount, and catalyst content generated a product with a slightly decreased molecular weight. The crystallinity of the terpolymer was investigated by differential scanning calorimetry and polarized optical microscopy. A reasonable mechanism for the polymerization was proposed based on the obtained results.展开更多
基金The project was supported by the National Natural Science Foundation of China(No.29774034).
文摘Poly-dl-lactide-poly(ethylene glycol) (PELA) triblock copolymers were synthesized with lanthanum acetate as the initiator. PELA microspheres with entrapped Vibrio Cholera antigen and outer membrane protein (OMP) were prepared by a double emulsion W/O/W based on solvent extraction methods. The obtained microspheres showed smooth and spherical surface and their size varied between 0.5 and 5.0 mu m, which are suitable for oral targeting delivery system. The distribution tests in rabbits and mice through scanning electronic micrography and fluorescence microscope indicated that microspheres have successfully reached the immunization-related tissues, such as the liver, spleen and intestinal peyer's patches, following oral administration. The PELA microspheres were also evaluated as an efficient antigen delivery system by enhancing a higher protective ratio against live Vibrios Cholera.
基金supported financially by the "Western Light" joint researcher program of Chinese Academy of Science
文摘In order to expand the application of poly（p-dioxanone） or PPDO in biomedical area,a series of novel copolymers were synthesized successfully by one-step,melted copolymerization of p-dioxanone（PDO） and L-phenylalanine N-carboxyanhydride（L-Phe-NCA） monomers.With the in-feed molar ratio of L-PheNCA /PDO equal to 1/20,the conversions of the two kinds of monomers were calculated from 1H NMR. The average molecular weight and polydispersity of the copolymer increase with the increasing reaction time and catalyst concentration.However,the conversions of the two kinds of monomers did not change with the reaction conditions.A three-step mechanism is presented and proved by high resolution 1H NMR and IR spectrums.
基金supported by the Western Light Joint Research Program of the Chinese Academy of Sciences
文摘In order to exploit the biological functions of materials, a series of new random terpolymers were synthesized by the ring-opening polymerization of p-dioxanone, trimethylene carbonate, and L-phenylalanine N-carboxyanhydride（L-PheNCA） in the presence of stannous octoate. The terpolymers were characterized by 1H-NMR, 13C-NMR, FTIR, and gel permeation chromatography. The effects of the reactant ratio, catalyst dosage, reaction temperature and time on the copolymerization were investigated, and were found to regulate the composition of the terpolymer. Increases in the reaction temperature, polymerization time, L-Phe-NCA monomer amount, and catalyst content generated a product with a slightly decreased molecular weight. The crystallinity of the terpolymer was investigated by differential scanning calorimetry and polarized optical microscopy. A reasonable mechanism for the polymerization was proposed based on the obtained results.
