Potential applications of PEI loaded graphene oxide quantum dots in safe and efficient DNA delivery

In order to improve the safety and efficacy of gene delivery using polyethyleneimine (PEI), this work focused on developing PEI quantum dots and incorporating them onto graphene to improve gene loading capacity. The successful creation of graphene-polyethyleneimine quantum dots (GPQDs) was confirmed through fluorescence emission spectrum and infrared spectroscopy. Both polyethyleneimine quantum dots (PQDs) and GPQDs exhibited blue fluorescence when excited between 310 and 430 nm, indicating that they retained the fluorescence characteristics of broad excitation and narrow emission. Furthermore, GPQDs displayed smaller particle sizes, increased hydrophilicity, and better dispersibility compared to PQDs. GPQDs were able to efficiently load DNA with lower cytotoxicity than PQDs and PEI. The enhanced fluorescence properties of GPQDs allowed for the observation that GPQDs/DNA complexes were effectively internalized by cells with higher uptake efficiency than PEI/DNA and PQDs/DNA complexes. The study demonstrated that GPQDs/DNA complexes successfully transfected 293T and HeLa cells, with GPQDs prepared using PEI25k showing improved cell uptake and transfection efficiency compared to those prepared with PEI10k. Overall, the findings suggest that GPQDs are a more effective and safer gene delivery vector than PEI, with promising potential for future gene delivery applications.