Bandgap-Tunable CeO_x@MnO_x Heterojunction for Modulable Sonodynamic and Chemodynamic Tumor Therapy

Area of Science:

• Biomedical Engineering
• Materials Science
• Oncology

Background:

• Sonodynamic therapy (SDT) is a promising non-invasive cancer treatment.
• Conventional sonosensitizers have limitations including wide bandgaps and poor tumor microenvironment responsiveness.
• These limitations lead to rapid electron-hole recombination and reduced efficacy.

Purpose of the Study:

• To design and synthesize novel CeO_x@MnO_x heterojunction nanomaterials (CM-1 to CM-4) for enhanced SDT.
• To investigate the effect of tunable MnO_x content on the performance of these heterojunctions.
• To explore the potential of these nanomaterials as a theranostic platform for cancer treatment.

Main Methods:

• Synthesis of CeO_x@MnO_x heterojunction nanomaterials with varying MnO_x content.
• Characterization of the nanomaterials' structure, bandgaps, and sonodynamic properties.
• Evaluation of CM-3's performance, including its bandgap, activity, and synergistic chemodynamic therapy potential.

Main Results:

• Heterojunction engineering successfully narrowed bandgaps and suppressed charge recombination in CeO_x@MnO_x nanomaterials.
• Sonodynamic performance was tunable based on MnO_x content, with CM-3 exhibiting optimal activity.
• CM-3 demonstrated synergistic chemodynamic therapy by producing reactive oxygen species and alleviating tumor hypoxia.

Conclusions:

• CeO_x@MnO_x heterojunctions represent a novel nanotheranostic platform for enhanced sonodynamic therapy.
• Bandgap engineering of heterojunctions is a viable strategy to improve SDT efficacy.
• This work provides a foundation for applying heterojunction band engineering in cancer treatment.