Xerion Healthcare’s nanoparticles are 50nm in size and consist of titanium dioxide combined with multiple rare earth elements. The nanoparticles are injected directly into the tumour and, because of their small size, disperse throughout the tumour and into the cancer cells through the cell membrane. Inside the cells the particles concentrate in cellular components and can remain there for a number of weeks.
Titanium dioxide is a semiconductor that has the unusual property of being highly photoactive – that is it generates free radicals using surface absorbed water and oxygen when excited by ultraviolet light. The rare earth elements incorporated into the nanoparticle allow high levels of photoactivity under X-rays as well. Once an external radiotherapy beam is applied the nanoparticles strongly interact with X-ray’s and electrons. Even in the absence of oxygen, water can be split generating hydroxyl free radicals and enhancing cancer cell death above that achievable with radiotherapy alone.
The result of this is that tumour growth is significantly suppressed, as demonstrated by in vivo mouse models. The nanoparticles are inert and non-toxic and have no effect without the X-rays. Under X-rays the growth rate post-treatment is over three times slower when Xerion Healthcare’s nanoparticles are added to the treatment regime.