Catalytically Active Ti-Based Nanomaterials for Hydroxyl Radical Mediated Clinical X-Ray Enhancement

Area of Science:

• Biomedical Engineering
• Materials Science
• Radiotherapy Research

Background:

• Nanoparticle radioenhancement aims to improve radiotherapy by increasing localized radiation damage in tumors.
• High atomic number nanomaterials (e.g., Au, HfO2) show reduced efficacy with clinical megavoltage X-rays compared to research orthovoltage X-rays.
• There is a need for nanomaterials that maintain radioenhancement effectiveness across a broad X-ray energy spectrum relevant to clinical settings.

Purpose of the Study:

• To design and investigate radiocatalytically active titanium-based nanomaterials for clinical X-ray therapy.
• To evaluate the radioenhancement performance of various titanium-based materials, including TiO2, metal-organic frameworks (MOFs), and MXenes, across different X-ray energy ranges.
• To understand the mechanism of radioenhancement, focusing on reactive oxygen species generation beyond physical dose enhancement.

Main Methods:

• Synthesis and characterization of titanium-based nanomaterials (TiO2, Ti-MOFs, Ti3C2Tx MXenes).
• Assessment of radioenhancement efficacy using orthovoltage and megavoltage X-ray sources.
• Evaluation of reactive oxygen species generation and cellular uptake in human soft tissue sarcoma and healthy fibroblast cells.
• Quantification of dose-enhancement factors in biological models.

Main Results:

• Titanium-based nanomaterials demonstrated consistent radioenhancement performance across orthovoltage and megavoltage X-ray energies.
• The observed enhancement is attributed to the catalytic generation of reactive oxygen species, a mechanism distinct from photoelectric effects.
• Titanium-based MOFs and MXenes achieved dose-enhancement factors of up to three in human soft tissue sarcoma cells.
• Selective enhancement was observed, with minimal impact on healthy human fibroblast cells, indicating targeted therapeutic potential.

Conclusions:

• Radiocatalytically active titanium-based nanomaterials are effective for radioenhancement in clinical X-ray therapy settings.
• These materials offer a sustained performance advantage over traditional high atomic number nanoparticles due to their mechanism of action.
• Titanium-based MOFs and MXenes represent promising candidates for developing novel, selective radiotherapy strategies with improved tumor targeting and reduced side effects.