Saponin and fluorine-modified polycation as a versatile gene delivery system

摘要

Despite the development of many novel carriers for the delivery of various types of genetic material, the lack of a delivery system with high efficiency and low cytotoxicity is a major bottleneck. Herein, low molecular weight polyethylenimine (PEI_(1.8k)) was functionalized with saponin residues using phenylboronic acid (PBA) as an ATP-responsive cross-linker, and a fluorinated side chain to construct PEI-PBA-SAP-F polycation as a highly efficient delivery vector. This vehicle could transfect small plasmid DNA (~3 kb) with outstanding efficiency into various cells, including HEK 293T, NIH3T3, A549, PC12, MCF7 and HT-29, as well as robust transfection of a large plasmid (~9 kb) into HEK 293T cells. The carrier indicated good transfection efficacy even at high concentration of serum and low doses of plasmid. The use of green fluorescent protein (GFP) knockout analysis demonstrated transfection of different types of CRISPR/Cas9 complexes (Cas9/sgRNA ribonucleoproteins RNP, plasmid encoding Cas9 plus sgRNA targeting GFP, Cas9 expression plasmid plus in vitro-prepared sgRNA). In summary, we report an effective PEI-PBA-SAP-F gene carrier with the appropriate lipophilic/cationic balance for biomedical applications.