Green-synthesized MnFe₂O₄/GO nanocomposites: structural characterization, cytotoxicity, and potential for targeted...

Cervical cancer remains a major global health challenge, with high mortality rates particularly in developing countries, and is often associated with poor prognosis in advanced stages. The limitations of conventional chemotherapeutics, such as systemic toxicity, poor targeting efficiency, and drug resistance, have prompted the exploration of nanotechnology-based therapeutic strategies. In this study, manganese ferrite (MnFe₂O₄) nanoparticles were synthesized via both chemical co-precipitation and a green hydrothermal method employing Urtica (nettle) extract as a natural reducing and stabilizing agent. Graphene oxide (GO) nanosheets were prepared through a modified Hummers method and integrated with MnFe₂O₄ to form MnFe₂O₄/GO nanocomposites. Physicochemical characterization using FT-IR, XRD, SEM-EDX, TEM, and DLS confirmed the successful synthesis of pure, crystalline spinel MnFe₂O₄ and its stable incorporation into GO matrices, with particle sizes in the nanoscale range and negative zeta potentials supporting colloidal stability. Magnetic measurements revealed superparamagnetic behavior for all samples, with saturation magnetization (Ms) values of 55 emu/g for pristine MnFe₂O₄, 40 emu/g for green-synthesized MnFe₂O₄, and 25 emu/g for MnFe₂O₄/GO, remaining within ranges suitable for magnetic targeting and hyperthermia. In vitro cytotoxicity against HeLa cells demonstrated enhanced anticancer activity for the MnFe₂O₄/GO composite (IC₅₀ = 120.7 µg/mL) compared to MnFe₂O₄ (IC₅₀ = 200.7 µg/mL) and GO (IC₅₀ = 1202 µg/mL), indicating a synergistic effect. qPCR analysis showed significant upregulation of pro-apoptotic genes (BAX, Caspase-3) and downregulation of the anti-apoptotic gene (Bcl-2), confirming apoptosis induction as a key mechanism of action. The results highlight MnFe₂O₄/GO nanocomposites as promising multifunctional platforms for targeted cervical cancer therapy, with combined magnetic responsiveness, structural stability, and potent pro-apoptotic activity.