AIM: To prepare chitosan-polyaspartic acid-5-fluorouracil (CTS-Pasp-5Fu) nanoparticles and investigate its anti-carcinoma effect and toxicity. METHODS: CTS-Pasp-5Fu nanoparticles were synthesized by ionic gelatificati...AIM: To prepare chitosan-polyaspartic acid-5-fluorouracil (CTS-Pasp-5Fu) nanoparticles and investigate its anti-carcinoma effect and toxicity. METHODS: CTS-Pasp-5Fu nanoparticles were synthesized by ionic gelatification. Male BABL/c nude mice were injected with SGC-7901 gastric carcinoma cell line mass to establish a human gastric carcinoma model. They were randomly allocated into 4 groups: CTS-Pasp-5Fu (containing 5-Fu 1.25 mg/kg), 5-Fu (1.25 mg/kg), CTS-Pasp and normal saline groups. Tumor weight was measured and assay of colony forming unit-granulocyte and macrophage (CFU-GM) was performed. The structural change of cells and tissues was observed and the Bax and Bcl-2 genes were detected. RESULTS: Compared with normal saline, the inhibition rates of tumor growth for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.58%, 58.69% and 70.82%, respectively. The tumor inhibition rates for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.09%, 65.3% and 72.79%, respectively. There was a significant decrease in the number of CFU-GMformation and increase of total bilirubin, and alanine aminotransferase in the 5-Fu group, but no change in those of the other three groups. There was no change in white blood cell count and creatinine among the four groups. Pathological section of liver and nephridial tissues showed that the damage in the 5-Fu group was more severe than that in the CTS-Pasp-5Fu group. 5-Fu and CTS-Pasp-5Fu groups could both down-regulate the Bcl-2 expression and up-regulate the Bax expression to different extent, and the accommodate effect of CTS-Pasp-5Fu was more obvious than 5-Fu. CONCLUSION: The tumor inhibition rate of CTS-Pasp-5Fu nanoparticles is much higher than that of 5-Fu alone.展开更多
Chitosan-graft-poly（L-glutamic acid）（CS-g-PGA） copolymer was successfully synthesized by grafting polymerization of γ-benzyl-L-glutamate N-carboxyanhydride onto the modified chitosan chains. The self-assembly beh...Chitosan-graft-poly（L-glutamic acid）（CS-g-PGA） copolymer was successfully synthesized by grafting polymerization of γ-benzyl-L-glutamate N-carboxyanhydride onto the modified chitosan chains. The self-assembly behavior of such a CS-g-PGA amphiphilic copolymer was studied. The results show that spherical nanoparticles have been formed. The size of CS-g-PGA nanoparticles is found to be controlled by the grafting ratio of PGA. These bio-based polysaccharide/polypeptide hybrid nanoparticles with controllable size may have great potential application in biomedical fields, such as drug delivery systems.展开更多
We report a considerably promising method based on agarose gel electrophoresis （AGE） to separate single-walled carbon nanotubes by adding a water-soluble polyfluorene （w-PFO） as surfactant into the agarose gel. In...We report a considerably promising method based on agarose gel electrophoresis （AGE） to separate single-walled carbon nanotubes by adding a water-soluble polyfluorene （w-PFO） as surfactant into the agarose gel. In this effective method, the AGE/w-PFO gel network will trap more semiconducting single-walled carbon nanotubes （SWNTs） with the assistance ofw-PFO, for the strong interaction between w-PFO and semiconducting species. The optical absorbance, photoluminescence emission and resonant Raman scattering characterization were used to ver- ify the separation effect. The purity of separated semiconducting species is as high as （98±1）%. The demonstrated field effect transistors give the on/off ratio and mobility about 27000 and 10.2 cm^2·V^-1·s^-1, respectively.展开更多
基金Shanghai Science and Technology Committee, No. 0452nm065
文摘AIM: To prepare chitosan-polyaspartic acid-5-fluorouracil (CTS-Pasp-5Fu) nanoparticles and investigate its anti-carcinoma effect and toxicity. METHODS: CTS-Pasp-5Fu nanoparticles were synthesized by ionic gelatification. Male BABL/c nude mice were injected with SGC-7901 gastric carcinoma cell line mass to establish a human gastric carcinoma model. They were randomly allocated into 4 groups: CTS-Pasp-5Fu (containing 5-Fu 1.25 mg/kg), 5-Fu (1.25 mg/kg), CTS-Pasp and normal saline groups. Tumor weight was measured and assay of colony forming unit-granulocyte and macrophage (CFU-GM) was performed. The structural change of cells and tissues was observed and the Bax and Bcl-2 genes were detected. RESULTS: Compared with normal saline, the inhibition rates of tumor growth for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.58%, 58.69% and 70.82%, respectively. The tumor inhibition rates for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.09%, 65.3% and 72.79%, respectively. There was a significant decrease in the number of CFU-GMformation and increase of total bilirubin, and alanine aminotransferase in the 5-Fu group, but no change in those of the other three groups. There was no change in white blood cell count and creatinine among the four groups. Pathological section of liver and nephridial tissues showed that the damage in the 5-Fu group was more severe than that in the CTS-Pasp-5Fu group. 5-Fu and CTS-Pasp-5Fu groups could both down-regulate the Bcl-2 expression and up-regulate the Bax expression to different extent, and the accommodate effect of CTS-Pasp-5Fu was more obvious than 5-Fu. CONCLUSION: The tumor inhibition rate of CTS-Pasp-5Fu nanoparticles is much higher than that of 5-Fu alone.
基金Supported by the National Natural Science Foundation of China(Nos.21034003, 20974025, 10979022)
文摘Chitosan-graft-poly（L-glutamic acid）（CS-g-PGA） copolymer was successfully synthesized by grafting polymerization of γ-benzyl-L-glutamate N-carboxyanhydride onto the modified chitosan chains. The self-assembly behavior of such a CS-g-PGA amphiphilic copolymer was studied. The results show that spherical nanoparticles have been formed. The size of CS-g-PGA nanoparticles is found to be controlled by the grafting ratio of PGA. These bio-based polysaccharide/polypeptide hybrid nanoparticles with controllable size may have great potential application in biomedical fields, such as drug delivery systems.
基金This work was financially supported by the National Natural Science Foundation of China （Nos. 21274027, 20974022） and the Innovation Program of Shanghai Municipal Education Commission （No. 15ZZ002）.
文摘We report a considerably promising method based on agarose gel electrophoresis （AGE） to separate single-walled carbon nanotubes by adding a water-soluble polyfluorene （w-PFO） as surfactant into the agarose gel. In this effective method, the AGE/w-PFO gel network will trap more semiconducting single-walled carbon nanotubes （SWNTs） with the assistance ofw-PFO, for the strong interaction between w-PFO and semiconducting species. The optical absorbance, photoluminescence emission and resonant Raman scattering characterization were used to ver- ify the separation effect. The purity of separated semiconducting species is as high as （98±1）%. The demonstrated field effect transistors give the on/off ratio and mobility about 27000 and 10.2 cm^2·V^-1·s^-1, respectively.
