研究了分子链中含有聚甲基丙烯酸(PMAA)链段的两亲性嵌段共聚物PS b PMAA和双亲水性嵌段共聚物PVP b PMAA,PVA b PMAA的溶液性质.结果显示,这些共聚物溶液都表现出明显的聚电解质溶液的性质,并且随着分子链中PMAA链段长度的增加,共聚物...研究了分子链中含有聚甲基丙烯酸(PMAA)链段的两亲性嵌段共聚物PS b PMAA和双亲水性嵌段共聚物PVP b PMAA,PVA b PMAA的溶液性质.结果显示,这些共聚物溶液都表现出明显的聚电解质溶液的性质,并且随着分子链中PMAA链段长度的增加,共聚物溶液的聚电解质溶液特征也随之增强,表明这些共聚物都是高分子电解质,其溶液粘度取决于其中MAA单元的比例.展开更多
Biodegradable triblock copolymer PLA/PEG/PLA was synthesized by ring-opening bulk polymerization of D,L-lactide in the presence of poly(ethylene glycol) (PEG), in the molecular structure of which, the length of PEG an...Biodegradable triblock copolymer PLA/PEG/PLA was synthesized by ring-opening bulk polymerization of D,L-lactide in the presence of poly(ethylene glycol) (PEG), in the molecular structure of which, the length of PEG and PLA chain segments was made to be quite different. Nanoparticles were prepared by using the copolymer via a double emulsion-evaporation technique. The paticles tended to form the configuration like capsules, i.e., the nanocapsules, because of the great size difference in PEG and PLA segments of the copolymer. Insulin, chosen as a model drug, was encapsulated into nanocapsules. The effect of preparation conditions on the size, insulin encapsulation efficiency, and in vitro drug release behavour of the nanoparticles were investigated. The experimental results show that the nanocapsules had a smooth spherical surface and the mean diameter was in the range from 180 nm to 350 nm, and the entrapment of insulin achieved up to 78.4. The drug-loaded nanocapsules released their content continuously, remarkably different from the corresponding micelles which gave a significant initial burst release followed by a slow release.展开更多
文摘研究了分子链中含有聚甲基丙烯酸(PMAA)链段的两亲性嵌段共聚物PS b PMAA和双亲水性嵌段共聚物PVP b PMAA,PVA b PMAA的溶液性质.结果显示,这些共聚物溶液都表现出明显的聚电解质溶液的性质,并且随着分子链中PMAA链段长度的增加,共聚物溶液的聚电解质溶液特征也随之增强,表明这些共聚物都是高分子电解质,其溶液粘度取决于其中MAA单元的比例.
文摘Biodegradable triblock copolymer PLA/PEG/PLA was synthesized by ring-opening bulk polymerization of D,L-lactide in the presence of poly(ethylene glycol) (PEG), in the molecular structure of which, the length of PEG and PLA chain segments was made to be quite different. Nanoparticles were prepared by using the copolymer via a double emulsion-evaporation technique. The paticles tended to form the configuration like capsules, i.e., the nanocapsules, because of the great size difference in PEG and PLA segments of the copolymer. Insulin, chosen as a model drug, was encapsulated into nanocapsules. The effect of preparation conditions on the size, insulin encapsulation efficiency, and in vitro drug release behavour of the nanoparticles were investigated. The experimental results show that the nanocapsules had a smooth spherical surface and the mean diameter was in the range from 180 nm to 350 nm, and the entrapment of insulin achieved up to 78.4. The drug-loaded nanocapsules released their content continuously, remarkably different from the corresponding micelles which gave a significant initial burst release followed by a slow release.
