Absorbing materials with applications in radiotherapy and radioprotection

The radiotherapy centres are using linear accelerators equipped with multi-leaf collimators (MLCs) for treatments of various types of cancer. For superficial cancers located at a maximum depth of 3 cm high-energy electrons are often used, but MLC cannot be used together with electron applicators. Due to the fact that the tumour shape is not square (as electron applicators), searching for different materials that can be used as absorbents or shields for the protection of adjacent organs is of paramount importance. This study presents an experimental study regarding the transmitted dose through some laboratory-made materials when subjected to electron beams of various energies (ranging from 6 to 15 MeV). The investigated samples were composite materials consisting of silicon rubber and micrometre aluminium particles with different thicknesses and various mass fraction of aluminium. The measurements were performed at a source surface distance of 100 cm in the acrylic phantom. The experimental results show that the transmitted dose through tested samples is ranging between ∼1.8 and 90%, depending on the electron beam energy, sample thickness and sample composition. These preliminary results suggest that the analysed materials can be used as absorbers or shields in different applications in radiotherapy and radioprotection.