摘要
Oleoylchitosans (O-chitosans) with different degrees of substitution (DS) were synthesized by reacting chitosan with oleoyl chloride. The chemical structures of the products were characterized by 1H NMR and FT-IR. These results suggested the for- mation of an amide linkage between the amino groups of chitosan and the carboxyl groups of oleic acid. The viscosity of O-chitosan sharply increased with the increase of concentration, whereas that of unmodified chitosan rose only slightly. This increase became larger as the DS increased. All of the O-chitosans could reduce surface tension slightly. The critical aggregation concentration (CAC) of O-chitosans with DS 5%, 11%, and 27% were 79.43 mgL-1, 31.6 mgL-1, and 10 mgL-1, respectively. Nanoparticles were prepared using an O/W emulsification method. The mean diameters of the polymeric amphiphilic nanoparticles of O-chitosans with DS 5% and 11% were around 327.4 nm and 275.3 nm, respectively.
Oleoylchitosans （O-chitosans） with different degrees of substitution （DS） were synthesized by reacting chitosan with oleoyl chloride. The chemical structures of the products were characterized by ^1H NMR and FT-IR. These results suggested the formation of an amide linkage between the amino groups of chitosan and the carboxyl groups of oleic acid. The viscosity of O-chitosan sharply increased with the increase of concentration, whereas that of unmodified chitosan rose only slightly. This increase became larger as the DS increased. All of the O-chitosans could reduce surface tension slightly. The critical aggregation concentration （CAC） of O-chitosans with DS 5%, 11%, and 27% were 79.43 mgL^-1, 31.6 mgL^-1, and 10mgL^-1, respectively. Nanoparticles were prepared using an O/W emulsification method. The mean diameters of the polymeric amphiphilic nanoparticles of O-chitosans with DS 5% and 11% were around 327.4 nm and 275.3 nm, respectively.
基金
financial support from the National Natural Science Foundation of China(No.30370344)
the Scientist Encouragement Foundation of Shandong Province(2004BS7001).
关键词
O-聚氨基葡萄糖
表面张力
荧光
乳酸
O-chitosan
viscosity
surface tension
fluorescence
nanoparticles
