摘要
通过二代和四代聚酰胺-胺树枝状聚合物(G2和G4表示)末端分别修饰苯丙氨酸和色氨酸合成了多种新型聚合物载体,进而考察了其与质粒的组装行为.研究结果显示,Phe-G4和Trp-G4与质粒组装为结构致密的纳米粒子,其中Phe-G4与质粒形成的纳米粒子更加紧密.这一过程是由聚合物载体与质粒间的静电相互作用和结构重排共同驱动的.此外,末端修饰方法显著降低了载体的细胞毒性.细胞转染结果表明,Phe-G4和Trp-G4成功介导质粒pEGFP-CL在COS-7细胞中表达,Phe-G4/pEGFP-CL的转染效率提高到作为阳性对照的脂质体组的4倍以上.因此,Phe-G4载体是一种有应用潜力的新型基因传递系统.
The high-efficient assembly of plasmid DNA by polymers has become important for successful delivery of gene materials into the target cells.In this research,four polymers were synthesized by coupling phenylalanine(Phe) and tryptophan(Trp) to poly(amidoamine) dendrimers of generation 2(G2) and 4(G4),respectively,so as to mimic the function of viral proteins.Then,the assembly of the plasmid DNA and polymeric vectors was investigated with agarose gel electrophoresis,ethidium bromide displacement assay and dynamic light scattering.The results indicated that Phe-G4 and Trp-G4 could self-assembly with the plasmid DNA to form more compact nano-sized particles with hydrodynamic radii of ca.40 nm.It was driven by electrostatic interaction and structural rearrangement.Moreover,Phe-G4 and Trp-G4 exhibited high cell viability in COS-7 cell lines,meaning low cell toxicity of the polymeric vectors.The plasmid pEGFP-CL was transfected successfully in vitro by both Phe-G4 and Trp-G4 and the transfection efficiency of Phe-G4/plasmid DNA polyplexs was over four-times higher than that of liposome-mediated delivery method.In concern with these results,it is confirmed that Phe-G4 is a potential candidate as a high-efficient gene delivery system.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2013年第8期1025-1032,共8页
Acta Polymerica Sinica
基金
国家自然科学基金(基金号20676099)
天津市应用基础研究计划(项目号09JCYBJC06800)资助
关键词
聚酰胺-胺树枝状聚合物
基因传递
质粒组装
光散射
恒温滴定量热
转染
Poly(amidoamine) dendrimers,Gene delivery,Plasmid assembly,Light scattering,Isothermal titration calorimetry,Transfection
