Scalable Synthesis of Ultrasmall Metal Oxide Radio-Enhancers Outperforming Gold

Nanoparticle-based radio-enhancement has the potential to improve cancer cell eradication by augmenting photoelectric cross-section of targeted cells relative healthy surroundings. Encouraging results have been reported for various nanomaterials, including gold and hafnia. However, lack scalable synthesis methods comparative studies is prohibitive rationalized material design hampers translation this promising management strategy. Here, we present a (>100 g day–1) sterile alternative conventional batch group IV metal oxides (TiO2, ZrO2, HfO2), which yields near-monodisperse ultrasmall oxide nanoparticles with properties. Access nanoparticles, solely differ in atomic number but otherwise exhibit comparable morphologies, sizes, surface chemistries, enables direct comparison their properties rationally guide selection optimal performance. We show that atomic-number-dependent (HT1080 HeLa), attenuated baseline levels normal fibroblasts (normal human dermal fibroblasts). The observed effects excellent agreement physical dose enhancement nanoparticle dosimetry calculations. Direct benchmarking against current standard field, rationalizes use hafnia based on performance, superior equi-sized nanoparticles. Taken together, competitive produced flame spray offer route overcoming key roadblocks nanoparticle-based radio-enhancers.