Facile synthesis and characterization of α-Fe2O3 and α-Fe3O4 nanoparticles with potential biomedical applications

Iron oxide nanoparticles (IONPs) have been extensively studied for biomedical applications; however, systematic comparison of phase-dependent physicochemical and biological properties under identical synthesis conditions remains limited. In the present study, α-Fe 2 O 3 and α-Fe 3 O 4 nanoparticles (IONPs) were synthesized via a co-precipitation method to investigate the influence of crystal structure on magnetic behavior and cytotoxicity. Structural and morphological characterization was performed using UV–visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX), confirming the formation of rhombohedral α-Fe 2 O 3 and cubic spinel α-Fe 3 O 4 nanoparticles with nanoscale particle sizes of 7.59 nm and 6.47 nm, respectively. Vibrating sample magnetometry (VSM) revealed superparamagnetic behavior in both nanoparticle systems, with saturation magnetization values of 12.02 emu/g for α-Fe 2 O 3 and 10.63 emu/g for α-Fe 3 O 4 , along with negligible coercivity and remanence. Zeta potential analysis indicated negatively charged nanoparticles with moderate colloidal stability. Cytotoxicity assessment using the MTT assay demonstrated concentration-dependent inhibition of tumor cell viability, with observable differences between IONPs, suggesting phase-dependent biological responses. In addition, in-silico ADMET and toxicity predictions using pkCSM, StopTox, and ProTox-II provided preliminary insights into the pharmacokinetic behavior and safety profile of the nanoparticles. Overall, this study highlights the influence of iron oxide phase composition on magnetic and cytotoxic properties, offering insights into the rational design of iron oxide-based nanomaterials for biomedical applications.