Design of DNA-coated hematite(α-Fe 2 O 3 ) nanoparticles with metformin conjugation for targeted anticancer activity

Non-viral gene delivery systems are gaining attention as safer alternatives to viral vectors, with iron oxide nanoparticles (Fe2O3NPs) emerging as promising candidates due to their magnetic responsiveness, biocompatibility, and surface tunability. In this study, DNA-coated Fe2O3 nanoparticles (Dhm) were synthesized via co-precipitation using fish DNA and further functionalized with Metformin (MFN). The synthesized nanoparticles exhibited quasi-spherical morphology with an average size of 94.7 nm and a ζ-potential of −43.78 mV, indicating excellent colloidal stability. Structural characterization by FTIR, FESEM, AFM, and XRD confirmed successful DNA coating and nanoparticle formation. The Dh/MFN formulation showed enhanced drug release, achieving 99.83 ± 0.5% MFN release within 8 h, compared to 98.56 ± 0.47% over 26 h for pure MFN. Additionally, Dh/MFN demonstrated improved antioxidant potential (DPPH IC50 = 24 ± 1.3) and the formulations exhibited a dose-dependent reduction (IC50 =31.2 ± 1.6 μM) in MCF-7 cell viability, indicating moderate antiproliferative activity.