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目的:基因方法治疗癌症近年来取得了很大的突破,因此基因载体的构建显得尤为重要。其中纳米基因载体合成简单,成本低廉,并能够包裹、浓缩、保护核苷酸使其免受核酸酶降解,因此纳米材料广泛地应用于基因输送。我们拟开展聚乙烯亚胺-纳米金基因载体的制备及其表征。方法:采用层层包裹技术制备基因载体,首先通过柠檬酸钠还原法制备纳米金颗粒后,应用11-巯基十一烷酸对金颗粒进行修饰,使其表面带有羧基,然后进一步将带有氨基的低分子量聚乙烯亚胺与羧基进行连接。应用动态光散射(DLS),紫外可见光谱(UV)和透射电子显微镜(TEM)对构建的纳米基因载体进行表征。结果:成功制备了聚乙烯亚胺-纳米金基因载体,检测表明每一步制备出的产物纳米尺寸在20-30 nm之间,液体均匀稳定,分散系数(PDI)在0.2以下,Zeta电位测定表明,每步的产物电荷变化与外层包裹的反应物有关。尽管金颗粒外层包裹聚乙烯亚胺,但是总体上纳米载体尺寸没有发生太大的变化,TEM检测表明每一步形成了均匀的、单分散的、球状的纳米颗粒。结论:我们通过层层包裹技术成功制备了聚乙烯亚胺-纳米金基因载体,在进一步开展的生物活性的检测中,希望通过纳米载体的携带作用,将基因转染进靶细胞,从而检测相关基因对靶细胞的沉默作用,提高基因药物的应用,为开发新型基因药物提供基础。
OBJECTIVE: Genetic methods for the treatment of cancer have made great breakthroughs in recent years. Therefore, the construction of gene vectors is particularly important. Among them, the nano-gene carrier is simple to synthesize, low in cost, and capable of wrapping, concentrating and protecting nucleotides from being degraded by nucleases. Therefore, nano-materials are widely used for gene delivery. We intend to carry out polyethyleneimine - nano gold gene vector preparation and characterization. METHODS: The gene vector was prepared by the layer-by-layer technique. Firstly, the gold nanoparticles were prepared by sodium citrate reduction method and then the gold particles were modified with 11-mercaptoundecanoic acid to form carboxyl groups on the surface. Then, The amino low molecular weight polyethyleneimine is attached to the carboxyl group. The constructed nano-gene vectors were characterized by dynamic light scattering (DLS), UV-visible spectroscopy (UV) and transmission electron microscopy (TEM). Results: Polyethyleneimine-nano gold gene vector was successfully prepared. The results showed that the nanosize size of each product was 20-30 nm, the liquid was stable and the PDI was less than 0.2. Zeta potential measurement showed that , Each step of the product charge changes and the outer package of reactants. Although the outer layer of gold particles encapsulated polyethyleneimine, the overall size of the nanocarrier did not change much and the TEM test showed that each step resulted in a uniform, monodisperse, spherical nanoparticle. CONCLUSION: We successfully prepared polyethyleneimine-nanogold gene vector by multilayer encapsulation technology. In further testing of biological activity, we hope to transfect the gene into target cells through the carrier effect of nanocarrier to detect the correlation Gene silencing of target cells, improve the application of gene drugs, and provide a basis for the development of new gene drugs.