Preparation and characterization of Fe3O4-spermine-PCL-chitosan-PEG-FA nanoparticles for DNA delivery into AGS cells

Gene therapy, a novel treatment approach for diseases such as cancer and genetic disorders, involves the transfer of genes to host cells or tissues. In recent decades, methods such as viruses, bacteria, and mechanical techniques have been utilized for gene transfer. However, Owing to the significant side effects of traditional methods for cancer treatment, especially chemotherapy, nanoparticles have emerged as a preferred alternative, enhancing targeted gene delivery and reducing complications. This study utilized copolymers such as spermine-chitosan-polycaprolactone (PCL) (PCS) and iron oxide nanoparticles (Fe3O4) to protect DNA and facilitate oligonucleotide transfer. Additionally, spermine-PCL-chitosan-polyethylene glycol (PEG)-folic acid (SPCPF) micelles were synthesized to control DNA release and target tumors. SCPPF/Fe3O4/DNA micelles were then prepared, and their properties, including protection against plasma degradation, ability to release DNA, physicochemical properties, transfection efficiency, and cytotoxicity, were evaluated in vitro. The study also investigated the impact of two buffer pH values (6 and 7.4) on DNA release from micelles, revealing that a lower pH significantly increased the release rate. Electrophoretic analysis confirmed that the micelle coating effectively protected DNA from degradation in plasma. VSM (vibrating sample magnetometer) analysis was used to assess the magnetic properties of the SCPPF/Fe3O4/DNA micelles, revealing that encapsulation with PCS and PCPF yielded nanoparticles with desirable magnetic characteristics. However, the encapsulation value reduced the saturation magnetic properties of the samples from 13.4 to 39.3 emu/g. Furthermore, the micelles significantly improved the DNA transfer efficiency compared with that of the polyethylenimine (PEI)/DNA complex in serum, achieving 14.42% efficiency with the SCPPF/Fe3O4/DNA micelles compared with 10.6% for the PEI/DNA complex. In terms of cytotoxicity, the SCPPF/Fe3O4 micelles exhibited low toxicity to the AGS cell line.