Methoxy poly(ethylene glycol)-poly(D,L-lactide) block copolymers (PEG-PLA) were prepared through ring-opening polymerization.The oil in water suspension method was used to prepare block copolymer micelles. The critica...Methoxy poly(ethylene glycol)-poly(D,L-lactide) block copolymers (PEG-PLA) were prepared through ring-opening polymerization.The oil in water suspension method was used to prepare block copolymer micelles. The critical micelle concentration (CMC) by fluorescence spectroscopy was 0.0056 mg·ml -1 . The physical state of the inner core region of micelles was characterized with 1HNMR. The size of indomethacin (IMC) loaded micelles measured by dynamic light scattering (DLS) showed narrow monodisperse size distribution and the average diameters were less than 50 nm. In addition, the nanoparticles with relatively high drug loading content (DLC) were obtained.展开更多
The solution property of amphiphilic graft copolymer has been examined by means of NMR,TEM and viscometry. It is found that water and toluene are selective solvent for PSt- g- PEO. When it is dissolved in water, micel...The solution property of amphiphilic graft copolymer has been examined by means of NMR,TEM and viscometry. It is found that water and toluene are selective solvent for PSt- g- PEO. When it is dissolved in water, micelle can be formed with hydrophobic PSt backbone as the core and hydrophilic PEO side chains as the shell. On the other hand, in selective solvent toluene, the reversed- micelle can be formed with PEO as core and PSt as the shell. In toluene, with an increase in concentration, the conformation of PSt- g- PEO can be transformed from stretched single molecule to spherical reversed- micelle. The critical micelle concentration(CMC) is determined at different temperature and with the increase of temperature and the content of PEO the reversed- micelle can be formed in lower concentrations.展开更多
文摘Methoxy poly(ethylene glycol)-poly(D,L-lactide) block copolymers (PEG-PLA) were prepared through ring-opening polymerization.The oil in water suspension method was used to prepare block copolymer micelles. The critical micelle concentration (CMC) by fluorescence spectroscopy was 0.0056 mg·ml -1 . The physical state of the inner core region of micelles was characterized with 1HNMR. The size of indomethacin (IMC) loaded micelles measured by dynamic light scattering (DLS) showed narrow monodisperse size distribution and the average diameters were less than 50 nm. In addition, the nanoparticles with relatively high drug loading content (DLC) were obtained.
文摘The solution property of amphiphilic graft copolymer has been examined by means of NMR,TEM and viscometry. It is found that water and toluene are selective solvent for PSt- g- PEO. When it is dissolved in water, micelle can be formed with hydrophobic PSt backbone as the core and hydrophilic PEO side chains as the shell. On the other hand, in selective solvent toluene, the reversed- micelle can be formed with PEO as core and PSt as the shell. In toluene, with an increase in concentration, the conformation of PSt- g- PEO can be transformed from stretched single molecule to spherical reversed- micelle. The critical micelle concentration(CMC) is determined at different temperature and with the increase of temperature and the content of PEO the reversed- micelle can be formed in lower concentrations.
