【摘要】 目的研究合成的非病毒基因载体材料PEG-PEI共聚物与DNA形成复合物的各项物理化学性能指标,为PEG-PEI共聚物作为非病毒基因载体介导体内外基因传递的研究奠定基础。方法将含PEG不同相对分子质量和接枝量的PEG-PEI共聚物,与DNA形成复合物。测定了PEG-PEI/DNA复合物的粒径、Zeta电位,结构形态、在水溶液中的溶解性及共聚物的缓冲容量,分析了接枝PEG对各项物理化学性能的影响。结果接枝了PEG后,PEG-PEI/DNA复合物的粒径都明显减小,Zeta电位有一定程度的下降,接枝相对分子质量较大的PEG可使Zeta电位下降较多,亲水链段PEG对降低粒子间的聚集和增加溶解性起到了关键性的作用。接枝PEG的量对引起的内含体破裂并释放DNA的质子海绵效应不会产生明显影响。结论形成PEG-PEI共聚物后,对PEI/DNA复合物的物理化学性能有一定的改善作用,使复合物更适宜用于体内基因转导。更多还原

【Abstract】 OBJECTIVE To study physicochemical property of PEG-PEI/DNA complexes so as to provide foundation to the research of PEG-PEI copolymers as carriers for gene delivery in vivo and in vitro.METHODS The PEG PEI /DNA complexes were formed with different molecular weight of PEG and degree of PEG-PEI copolymer.The complex size,Zeta potential,morphology,solubility of copolymer/DNA complexes and buffering capacity of PEG-PEI copolymer were measured,and the effection of PEG-PEI copolymer on the physicochemical property of DNA complexes was investigated.RESULTS After PEG-PEI coplymer,particle sizes of PEG-PEI/DNA complexes evidently decreased,and Zeta potential decreased to a certain extent.The longer the PEG chain,the lower zeta potential of the complexes.Hydrophilic PEG in copolymer was very important for reducing aggregation between particles and increasing solubility.The degree of PEG-PEI copolymer had no obvious influence on the disruption of endosomal compartments and DNA releasing from endosomes via the proton sponge mechanism.CONCLUSION After PEG-PEI copolymer,the physicochemical property of PEI/DNA complexes could be improved,and could be used in gene delivery in vivo.更多还原