Targeted delivery of interleukin‐12 plasmid into HepG2 cells through folic acid conjugated graphene oxide nanocarrier

Abstract Successful gene therapy relies on carriers to transfer genetic materials with high efficiency and low toxicity in a targeted manner. To enhance targeted cell binding and uptake, we developed and synthesized a new gene delivery vector based on graphene oxide (GO) modified by branched polyethyleneimine (BPEI) and folic acid (FA). The GO‐PEI‐FA nanocarriers exhibit lower toxicity compared to unmodified PEI, as well as having the potential to efficiently condense and protect pDNA. Interestingly, increasing the polymer content in the polyplex formulation improved plasmid transfer ability. Substituting graphene oxide for PEI at an N/P ratio of 10 in the HepG2 and THP1 cell lines improved hIL‐12 expression by up to approximately eightfold compared to simple PEI, which is twice as high as GO‐PEI‐FA in Hek293 at the same N/P ratio. Therefore, the GO‐PEI‐FA described in this study may serve as a targeting nanocarrier for the delivery of the hIL‐12 plasmid into cells overexpressing folic acid receptors, such as those found in hepatocellular carcinoma.