Self-association behavior of an amphiphilic polypeptide graft copolymer,poly(γ-benzyl L-glutamate)-g-poly(ethylene glycol), and the drug carrier capability of the formed micelles were examined by fluorescence spectro...Self-association behavior of an amphiphilic polypeptide graft copolymer,poly(γ-benzyl L-glutamate)-g-poly(ethylene glycol), and the drug carrier capability of the formed micelles were examined by fluorescence spectroscopy,transmission electron microscopy and UV spectroscopy.It was found that the hydrophobic inner core of the micelles formed by poly(γbenzyl L-glutamate)(PBLG) segments can act as an incorporation site for hydrophobic drugs.The drug-loading content of the graft copolymer micelles tends to be larger when the content of the PBLG segments in the copolymer increases.The results obtained from the drug-release studies showed that the drug-release rates were dependent on the chemical nature of the graft copolymer.展开更多
Triphosgene was used to react with γ-chloroethyl glutamate, which was synthesized from 2-ethylene chlorohydrin and L-glutamic acid, to give γ-chloroethyl glutamate N-carboxyan.hydride (NCA). Thus, poly(γ-chloroethy...Triphosgene was used to react with γ-chloroethyl glutamate, which was synthesized from 2-ethylene chlorohydrin and L-glutamic acid, to give γ-chloroethyl glutamate N-carboxyan.hydride (NCA). Thus, poly(γ-chloroethyl glutamate), a new poly (amino acid) with reactive chloride, was obtained from the NCA by using triethylamine as the initiator which can lead to intrinsic viscosity of polypeptide, [η], over 50 mL/g. NCA and polymer were characterized by IR, 1H NMR and 13C NMR. Oligomer of γ-chloroethyl glutamate was also obtained while NCA was initiated by moisture in air. The conforma- tions of oligomer and polymer of γ-chloroethyl glutamate were observed by IR and CD spectroscopy. The results suggested that the conformation of oligomer mainly be β-sheet, while the polymer be α-helix.展开更多
文摘Self-association behavior of an amphiphilic polypeptide graft copolymer,poly(γ-benzyl L-glutamate)-g-poly(ethylene glycol), and the drug carrier capability of the formed micelles were examined by fluorescence spectroscopy,transmission electron microscopy and UV spectroscopy.It was found that the hydrophobic inner core of the micelles formed by poly(γbenzyl L-glutamate)(PBLG) segments can act as an incorporation site for hydrophobic drugs.The drug-loading content of the graft copolymer micelles tends to be larger when the content of the PBLG segments in the copolymer increases.The results obtained from the drug-release studies showed that the drug-release rates were dependent on the chemical nature of the graft copolymer.
文摘Triphosgene was used to react with γ-chloroethyl glutamate, which was synthesized from 2-ethylene chlorohydrin and L-glutamic acid, to give γ-chloroethyl glutamate N-carboxyan.hydride (NCA). Thus, poly(γ-chloroethyl glutamate), a new poly (amino acid) with reactive chloride, was obtained from the NCA by using triethylamine as the initiator which can lead to intrinsic viscosity of polypeptide, [η], over 50 mL/g. NCA and polymer were characterized by IR, 1H NMR and 13C NMR. Oligomer of γ-chloroethyl glutamate was also obtained while NCA was initiated by moisture in air. The conforma- tions of oligomer and polymer of γ-chloroethyl glutamate were observed by IR and CD spectroscopy. The results suggested that the conformation of oligomer mainly be β-sheet, while the polymer be α-helix.