Engineering Hafnium Oxide‐Based Nanoplatforms for Precision Radiosensitization

ABSTRACT Hafnium oxide (HfO 2 )‐based nanomaterials are emerging as powerful tools to enhance radiotherapy by utilizing their high atomic number (Z). By depositing a greater radiation dose directly within tumors, they offer a promising route to improve treatment efficacy. This review traces the development of HfO 2 nanoradiosensitizers, starting with the clinically established NBTXR3, an approved hafnium‐based benchmark for several solid tumors. We analyze the structural characteristics and radiosensitization mechanisms of nanoscale HfO 2 , which include improved X‐ray absorption, radical generation, and immunomodulation. Key synthesis methods such as sol–gel, precipitation, and hydrothermal approaches are evaluated in detail, with emphasis on their tunable parameters and reproducibility. Recent progress focuses on material optimization through size control, surface engineering, composite design, and Hf‐MOFs, as well as combination strategies. Despite encouraging preclinical results, challenges remain in scalable fabrication, long‐term biosafety, and clinical translation. Future directions point toward smart stimuli‐responsive platforms and multimodal theranostic systems. This review highlights the potential of HfO 2 to precision radiotherapy while acknowledging existing translational challenges.