目的合成聚乙二醇单甲醚-聚乳酸(mPEG-PDLLA)嵌段共聚物,制备去氧鬼臼毒素mPEG-PDLLA嵌段共聚物(DPT-PM),提高去氧鬼臼毒素在水中的溶解度。方法以开环聚合反应合成mPEG-PDLLA,并通过IR、1H-HMR确证其结构,芘荧光探针法测定其临界胶束浓...目的合成聚乙二醇单甲醚-聚乳酸(mPEG-PDLLA)嵌段共聚物,制备去氧鬼臼毒素mPEG-PDLLA嵌段共聚物(DPT-PM),提高去氧鬼臼毒素在水中的溶解度。方法以开环聚合反应合成mPEG-PDLLA,并通过IR、1H-HMR确证其结构,芘荧光探针法测定其临界胶束浓度(CMC);采用溶剂蒸发法制备DPT-PM溶液,并将其冷冻干燥;分别采用动态光散射法(DLS)、透射电子显微镜(TEM)、差示扫描量热法(DSC)、高效液相色谱法(HPLC)等手段对胶束形态、粒径与分布、载药量、包封率等进行表征,并采用透析法考察DPT-PM体外释放,并对释放机制进行探讨。结果制备了去氧鬼臼毒素共聚物胶束,透射电镜下观察为近球形,平均粒径为22.0±8.9nm,载药量为20.67%,包封率为99.63%。结论 m PEG-PDLLA聚合物胶束可作为疏水性药物去氧鬼臼毒素的载体,具有较高的载药性能,能一定程度提高去氧鬼臼毒素在水中的溶解度。展开更多
PLGA, m PEG diblock copolymer was synthesized by bulk ring-opening polymerization method. The double emulsion solvent evaporation method was used to prepare bovine serum albumin（BSA）-loaded microspheres. Optical mic...PLGA, m PEG diblock copolymer was synthesized by bulk ring-opening polymerization method. The double emulsion solvent evaporation method was used to prepare bovine serum albumin（BSA）-loaded microspheres. Optical microscopy was used to observe the whole microsphere fabrication process. It is confirmed that the proportion of inner aqueous phase is one of the most critical factors that determines the morphology of microspheres. Double emulsion droplets which have appropriate amount of inner aqueous phase can form closed and dense microspheres, while, too much inner aqueous phase will cause a collapse of the double emulsion droplets, resulting in a loss of drug. The proportion of inner aqueous phase was varied to prepare microspheres of different morphology. The results show that with increasing the amount of inner aqueous phase, a higher percent of broken microspheres and lower encapsulation efficiency appeared, and also, a more severe initial burst release and faster release rate.展开更多
Protoplast fusion was induced between sainfoin and alfalfa by an improved polyethyleneglycol (PEG) method. The intergeneric somatic calluses were selected based on complementation of hydroxyproline-resistance of sainf...Protoplast fusion was induced between sainfoin and alfalfa by an improved polyethyleneglycol (PEG) method. The intergeneric somatic calluses were selected based on complementation of hydroxyproline-resistance of sainfoin and hormone autonomy growth of alfalfa transformation cell line. 17 somatic hybrid plantlets were regenerat-ed. PEG could induce the tight agglutination of protoplasts. During diluting and washing process, cyclization of the linked membrane and formation of vesicle-like structures were observed, resulting in protoplast fusion. 5%-10% glycerol supplemented in the fusion inducing solution markedly increased the frequency of heterogeneous fusion. Better fusion results were obtained when mixed protoplast suspension was dripped in petri dishes in which PEG solution was previously placed. Chromosome number of regenerated hybrid buds varied from 30 to 60. The genome of hybrids in-cluded the small chromosome from sainfoin and two chromosomes with two clear constrictions from alfalfa. The hybrid-ity of obtained hybrid calluses was confirmed by their isozyme banding patterns and their nopaline synthetase activity.展开更多
文摘目的合成聚乙二醇单甲醚-聚乳酸(mPEG-PDLLA)嵌段共聚物,制备去氧鬼臼毒素mPEG-PDLLA嵌段共聚物(DPT-PM),提高去氧鬼臼毒素在水中的溶解度。方法以开环聚合反应合成mPEG-PDLLA,并通过IR、1H-HMR确证其结构,芘荧光探针法测定其临界胶束浓度(CMC);采用溶剂蒸发法制备DPT-PM溶液,并将其冷冻干燥;分别采用动态光散射法(DLS)、透射电子显微镜(TEM)、差示扫描量热法(DSC)、高效液相色谱法(HPLC)等手段对胶束形态、粒径与分布、载药量、包封率等进行表征,并采用透析法考察DPT-PM体外释放,并对释放机制进行探讨。结果制备了去氧鬼臼毒素共聚物胶束,透射电镜下观察为近球形,平均粒径为22.0±8.9nm,载药量为20.67%,包封率为99.63%。结论 m PEG-PDLLA聚合物胶束可作为疏水性药物去氧鬼臼毒素的载体,具有较高的载药性能,能一定程度提高去氧鬼臼毒素在水中的溶解度。
基金financially supported by the Independent Innovation Foundation of Huazhong University of Science and Technology(No.2013ZHYX008)the National Natural Science Foundation of China(No.81370980)
文摘PLGA, m PEG diblock copolymer was synthesized by bulk ring-opening polymerization method. The double emulsion solvent evaporation method was used to prepare bovine serum albumin（BSA）-loaded microspheres. Optical microscopy was used to observe the whole microsphere fabrication process. It is confirmed that the proportion of inner aqueous phase is one of the most critical factors that determines the morphology of microspheres. Double emulsion droplets which have appropriate amount of inner aqueous phase can form closed and dense microspheres, while, too much inner aqueous phase will cause a collapse of the double emulsion droplets, resulting in a loss of drug. The proportion of inner aqueous phase was varied to prepare microspheres of different morphology. The results show that with increasing the amount of inner aqueous phase, a higher percent of broken microspheres and lower encapsulation efficiency appeared, and also, a more severe initial burst release and faster release rate.
基金Project supported by the National Natural Science Foundation of China.
文摘Protoplast fusion was induced between sainfoin and alfalfa by an improved polyethyleneglycol (PEG) method. The intergeneric somatic calluses were selected based on complementation of hydroxyproline-resistance of sainfoin and hormone autonomy growth of alfalfa transformation cell line. 17 somatic hybrid plantlets were regenerat-ed. PEG could induce the tight agglutination of protoplasts. During diluting and washing process, cyclization of the linked membrane and formation of vesicle-like structures were observed, resulting in protoplast fusion. 5%-10% glycerol supplemented in the fusion inducing solution markedly increased the frequency of heterogeneous fusion. Better fusion results were obtained when mixed protoplast suspension was dripped in petri dishes in which PEG solution was previously placed. Chromosome number of regenerated hybrid buds varied from 30 to 60. The genome of hybrids in-cluded the small chromosome from sainfoin and two chromosomes with two clear constrictions from alfalfa. The hybrid-ity of obtained hybrid calluses was confirmed by their isozyme banding patterns and their nopaline synthetase activity.
