The work described the synthesis and evaluation of PEI-g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and ...The work described the synthesis and evaluation of PEI-g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5 （mol/mol）. The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.展开更多
A new adsorbent was synthesized using polyethylenimine(PEI)on the carbon black to remove aspirin from an aqueous solution.In this study,adsorption performance of modified carbon black by polyethylenimine(PEI)on aspiri...A new adsorbent was synthesized using polyethylenimine(PEI)on the carbon black to remove aspirin from an aqueous solution.In this study,adsorption performance of modified carbon black by polyethylenimine(PEI)on aspirin was investigated.Batch adsorption studies were performed to evaluate the effects of contact time,pH solution,temperature,and initial concentration on the adsorption of aspirin.For this study,the carbon black obtained from the pyrolysis of tire waste was used as a precursor for low-cost adsorbents.The carbon black was treated by 1 M of hydrochloric acid solution to remove ash and sulphur content.Then,the treated carbon black was modified by impregnation with PEI in one to one weight ratio within 24 hours at 65°C and then cross linked with 1%(w/v)glutaraldehyde solution for one hour.The adsorption rate of aspirin by modified carbon black was rapid from 20 minutes to 60 minutes and reached equilibrium.Hence,the optimum contact time for this study is 60 minutes with 59.96%of aspirin removal and 29.98 mg/g adsorption capacity.The best performance for pH solution,temperature,and initial concentration was observed at pH 3(26.1 mg/g),30°C(26.9 mg/g)and 20 ppm(40.96 mg/g)respectively.展开更多
Objective: To construct a novel kind of nonviral gene delivery vector based on polyethylenimine (PEI) conjugated with polypeptides derived from ligand FGF with high transfection efficiency and according to tumor targe...Objective: To construct a novel kind of nonviral gene delivery vector based on polyethylenimine (PEI) conjugated with polypeptides derived from ligand FGF with high transfection efficiency and according to tumor targeting ability. Methods: The synthetic polypeptides CR16 for binding FGF receptors was conjugated to PEI and the characters of the polypeptides in-cluding DNA condensing and particle size were determined. Enhanced efficiency and the targeting specificity of the synthesized vector were investigated in vitro and in vivo. Results: The polypeptides were successfully coupled to PEI. The new vectors PEI-CR16 could efficiently condense pDNA into particles with around 200 nm diameter. The PEI-CR16/pDNA polyplexes showed significantly greater transgene activity than PEI/pDNA in FGF receptors positive tumor cells in vitro and in vivo gene transfer, while no difference was observed in FGF receptors negative tumor cells. The enhanced transfection efficiency of PEI-CR16 could be blocked by excess free polypeptides. Conclusion: The synthesized vector could improve the efficiency of gene transfer and targeting specificity in FGF receptors positive cells. The vector had good prospect for use in cancer gene therapy.展开更多
文摘The work described the synthesis and evaluation of PEI-g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5 （mol/mol）. The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.
文摘A new adsorbent was synthesized using polyethylenimine(PEI)on the carbon black to remove aspirin from an aqueous solution.In this study,adsorption performance of modified carbon black by polyethylenimine(PEI)on aspirin was investigated.Batch adsorption studies were performed to evaluate the effects of contact time,pH solution,temperature,and initial concentration on the adsorption of aspirin.For this study,the carbon black obtained from the pyrolysis of tire waste was used as a precursor for low-cost adsorbents.The carbon black was treated by 1 M of hydrochloric acid solution to remove ash and sulphur content.Then,the treated carbon black was modified by impregnation with PEI in one to one weight ratio within 24 hours at 65°C and then cross linked with 1%(w/v)glutaraldehyde solution for one hour.The adsorption rate of aspirin by modified carbon black was rapid from 20 minutes to 60 minutes and reached equilibrium.Hence,the optimum contact time for this study is 60 minutes with 59.96%of aspirin removal and 29.98 mg/g adsorption capacity.The best performance for pH solution,temperature,and initial concentration was observed at pH 3(26.1 mg/g),30°C(26.9 mg/g)and 20 ppm(40.96 mg/g)respectively.
基金Project (Nos. 2001AA217071 and 2003AA216041) supported by the Hi-Tech Research and Development Program (863) of China
文摘Objective: To construct a novel kind of nonviral gene delivery vector based on polyethylenimine (PEI) conjugated with polypeptides derived from ligand FGF with high transfection efficiency and according to tumor targeting ability. Methods: The synthetic polypeptides CR16 for binding FGF receptors was conjugated to PEI and the characters of the polypeptides in-cluding DNA condensing and particle size were determined. Enhanced efficiency and the targeting specificity of the synthesized vector were investigated in vitro and in vivo. Results: The polypeptides were successfully coupled to PEI. The new vectors PEI-CR16 could efficiently condense pDNA into particles with around 200 nm diameter. The PEI-CR16/pDNA polyplexes showed significantly greater transgene activity than PEI/pDNA in FGF receptors positive tumor cells in vitro and in vivo gene transfer, while no difference was observed in FGF receptors negative tumor cells. The enhanced transfection efficiency of PEI-CR16 could be blocked by excess free polypeptides. Conclusion: The synthesized vector could improve the efficiency of gene transfer and targeting specificity in FGF receptors positive cells. The vector had good prospect for use in cancer gene therapy.
