聚乙烯亚胺-聚乙二醇-siRNA纳米复合物的制备和理化性质的研究

Objective To investigate the preparation method and characteristics of polyethyleneimine- polyethylene glycal (PEI- PEG) siRNA nanocomplex to improve the cell transfection efficiency of siRNA. Methods PEI-PEG copolymer was synthesized as gene carrier and complexed with siRNA targeting to CD44v6 to form PEI-PEG-siRNA nanoparticle. The size and zeta potential was measured. The morphology of the complex was observed by scanning electron microscopy. The complex abilities of the nanocomplex were validated by gel retardation assay. And the transfection efficiency of nanocomplexes at different N/P ratios was measured by flow cytometry. Results The nanoparticles appeared spherical,uniform in size, and well-dispersed. When N/P ratio was over 10, the size of nanocomplex decreased as N/P value increased. Meanwhile, the zeta potential was positive and increased. At this time, siRNA was completely complexed with PEI-PEG, producing a fluorescence quenching phenomenon. The flow cytometry showed that the transfection efficiency of nanocomplexes was improved as N/P value increasied. When N/P was 30, the transfection efficiency was (75.6±9.2)%. Conclusion PEI-PEG may be a promised gene carrier and can provide evidences for related research of PEI-PEG-siRNA nanoparticles in animals and in vitro experiments.

Preparation of polyethyleneimine- polyethylene glycal- siRNA nanoparticle and investigation of its characteristics