Small-interfering RNA (siRNA) can specifically silence disease gene expression, bringing hope for the effective treatment of gene-related diseases. However, its use in vivo is limited due to the lack of efficient carriers. Therefore, it is necessary to construct carriers with high efficiency, low toxicity and serum stability. As a promising polycation carrier, polyethylenimine (PEI) can be further modified with a fluorine-containing alkyl chain that brings hydrophobic and oleophobic characteristics to its surface. In this study, low molecular weight PEI 1.8 kDa was selected and fluorinated through an anhydride reaction, and the product was named PEIF. In vitro experiments have shown that PEIF/siRNA polyplexes have suitable and stable particle size and potential, compress nucleic acids at a very low w/w ratio, and have the ability to effectively silence specific genes with low cytotoxicity. Compared with the polyplexes prepared using PEI 25 kDa, the PEIF/siRNA polyplexes were more stable in serum, showed a better antiangiogenic ability in in vivo experiments, and had a better tumor inhibition effect. The above results indicate that fluoropolymers based on the fluorine effect have great potential as gene delivery carriers for tumor therapy.

小干扰RNA（siRNA）可以特异性沉默疾病基因的表达，为基因相关疾病的有效治疗带来希望。然而，由于缺乏有效的载体，其在体内的使用受到限制。因此，有必要构建具有高效率，低毒性和血清稳定性的载体。作为有前途的聚阳离子载体，聚乙烯亚胺（PEI）可以用含氟烷基链进一步修饰，该烷基链为其表面带来疏水和疏油特性。在这项研究中，选择了1.8 kDa的低分子量PEI，并通过酸酐反应对其进行了氟化处理，并将该产物命名为PEIF。体外实验表明，PEIF / siRNA复合物具有合适且稳定的粒径和潜力，可在非常低的w / w下压缩核酸w比，并具有有效沉默具有低细胞毒性的特定基因的能力。与使用PEI 25 kDa制备的复合物相比，PEIF / siRNA复合物在血清中更稳定，在体内实验中显示出更好的抗血管生成能力，并且具有更好的肿瘤抑制作用。以上结果表明，基于氟效应的含氟聚合物作为肿瘤治疗的基因传递载体具有巨大的潜力。