Sulfur-33 nanoparticles: a Monte Carlo study of their potential as neutron capturers for enhancing boron neutron capture therapy of cancer.

In this paper, the potential effect of enhancing BNCT near the surface of the target volume by means of the addition of the sulfur isotope (33)S is studied. By means of Monte Carlo simulations, it is found a noticeable enhancement effect (local increase of the dose at the isotope site) when it is present at local concentrations that in principle can be reached by means of sulfur nanoparticles. A neutron beam with a high component of 13.5 keV would be required to produce this effect. Some open problems are discussed.