Theranostic Angiopep-2-Conjugated FeTaO _<i>x</i> @Au Core–Shell Magnetic Nanoparticles for Glioma Treatment and Dual Medical Imaging

In this work, iron-tantalum oxide nanoparticles (FeTaO_<i>x</i> NPs) with a gold coating modified by Angiopep-2 (FeTaO_<i>x</i>@Au-ANG) were developed to achieve dual-modality imaging and magnetically induced hyperthermia therapy for glioma. The 13.5 nm sized FeTaO_<i>x</i>@Au-ANG NPs' exhibited superparamagnetic behavior with excellent dual <i>T</i>₁/<i>T</i>₂-weighted MRI contrast of Fe existence and enhanced X-ray attenuation for computed tomography (CT) imaging, enabling accurate tumor localization through complementary imaging modalities. The incorporation of Ta and Au not only improved biocompatibility but also provided a high CT contrast effect. Upon magnetic stimulation, the NPs efficiently elevated the intratumoral temperature, leading to a significant (∼90%) reduction in glioma cell viability. ANG modification further enhanced the targeted uptake of NPs by glioma cells. Immunohistochemical analysis revealed extensive coagulative and glial necrosis, elevated GFAP expression, and a reduced Ki67 index, consistent with effective tumor ablation. <i>In vivo</i>, FeTaO_<i>x</i>@Au-ANG NPs treatment markedly suppressed tumor growth and extended survival by 18 days. Overall, this multifunctional nanoplatform demonstrates synergistic MRI/CT imaging-guided magnetic hyperthermia with high therapeutic efficacy and minimal side effects, offering strong potential for clinical cancer theranostics.