Nano Iron-copper alloys for tumor ablation: efficiently amplified oxidative stress through acid response

Efficiently enhancing intracellular oxidative stress via increasing intracellular hydroxyl radicals (•OH) which is based on the Fenton reaction and lowering glutathione (GSH) is a promising approach for cancer treatment. Herein, we synthesized a new alloy nanomaterial Fe5Cu3O@BSA (FCB) with the good dispersity with the aim to introduce copper ions to improve Fenton reaction efficiency and reduce GSH. Under the weak acid microenvironment at the tumor, FCB can release Fe2+ and Cu2+, and the released free electrons are expected to combine with oxygen to further generate H2O2, leading to excessive production of H2O2 in the cells. Meanwhile, released Fe2+ and Cu2+ can not only perform a higher reaction efficiency on producing •OH but also consume GSH, which dramatically increases the intracellular oxidative stress in both directions. In vitro experiments showed that incubation of human breast cancer cells (MCF-7 cells) with 100 μg/mL FCB nanoparticles resulted in a 65.9% mortality rate after 24 hours. And In vivo experiments showed FCB could effectively inhibit tumor growth. In this study, a therapeutic strategy based on metal biomaterials with good biocompatibility was established to effectively enhance oxidative stress, which has a great potential in tumor treatment.