Hierarchically decorated magnetic nanoparticles amplify the oxidative stress and promote the chemodynamic/magnetic hyperthermia/immune therapy.

Magnetic nanoparticles (MNPs) are promising in tumor treatments due to their capacity for magnetic hyperthermia therapy (MHT), chemodynamic therapy (CDT), and immuno-related therapies, but still suffer from unsatisfactory tumor inhibition in the clinic. Insufficient hydrogen peroxide supply, glutathione-induced resistance, and high-density extracellular matrix (ECM) are the barriers. Herein, we hierarchically decorated MNPs with disulfide bonds (S-S), dendritic L-arginine (R), and glucose oxidase (GOx) to form a nanosystem (MNPs-SS-R-GOx). Its outer GOx layer not only enhanced the HO supply to produce OH by Fenton reaction, but also generated stronger oxidants (ONOO) together with the interfaced R layer. The inner S-S layer consumed glutathione to interdict its reaction with oxidants, thus enhancing CDT effects. Importantly, the generated ONOO tripled the MMP-9 expression to induce ECM degradation, enabling much deeper penetration of MNPs and benefiting CDT, MHT, and immunotherapy. Finally, the MNPs-SS-R-GOx demonstrated a remarkable 91.7% tumor inhibition in vivo. STATEMENT OF SIGNIFICANCE: Magnetic nanoparticles (MNPs) are a promising tumor therapeutic agent but with limited effectiveness. Our hierarchical MNP design features disulfide bonds (S-S), dendritic L-arginine (R), and glucose oxidase (GOx), which boosts HO supply for ·OH generation in Fenton reactions, produces potent ONOO, and enhances chemodynamic therapy via glutathione consumption. Moreover, the ONOO facilitates the upregulation of matrix metalloprotein expression beneficial for extracellular matrix degradation, which in turn enhances the penetration of MNPs and benefits the antitumor CDT/MHT/immuno-related therapy. In vivo experiments have demonstrated an impressive 91.7% inhibition of tumor growth. This hierarchical design offers groundbreaking insights for further advancements in MNP-based tumor therapy. Its implications extend to a broader audience, encompassing those interested in material science, biology, oncology, and beyond.