EVALUATION OF PROTECTIVE EFFECT OF NEW HYBRID NANOCOMPOSITE LAYERS AGAINST X-RAYS USED IN MAMMOGRAPHY

In mammography absorbed dose is insignificant. Biologically, in normal people,
the phenomenon of hypersensitivity to low doses occurs. The purpose of this study was to investigate
the synergistic of Single-Walled Carbon Nanotube (SWCNT) in the polymer substrate of Poly Dimethyl
Siloxane (PDMS) in common energy in mammography.
Materials & Methods: Cerium oxide nanoparticles and SWCNT were added into the PDMS polymer in
order to fabricate 15 layers of nanocomposites. The dispersion of nanoparticles in the polymer was
investigated by Field Emission Scanning Electron Microscopy (FE-SEM). At mammography unit of
Motahari Hospital, the nanocomposites were irradiated with 28 kV tube potential. The radiation
characteristics were then recorded by the piranha dosimeter. The results of radiation attenuation were
calculated. Statistical analysis with Kruskal-Wallis test was performed with a significance level of less
than 0.05.
Results: The results of the FE-SEM showed the excellent dispersion of nanoparticles. It indicated the
accuracy of the range (10-30 nm) of particle diameter. The characteristic of the beam quality (0.338 mm
Al) was correctly within the defined range. The statistical analysis resulted in a P-value of 0.027, which
it indicated a significant difference in the amount attenuation of nanocomposites. By adding SWCNT
into samples, the absorption was increased by up to 3%. The most important achievement was a 12%
reduction in weight, for hybrid nanocomposites (25% cerium oxide nanoparticles + SWCNT) than those
that contained only 25% of the cerium oxide.
Conclusion: The results showed that cerium oxide, based on PDMS, is able to attenuate X-rays. In
addition, single-wall carbon nanotubes can be effective in improving the effectiveness of protective
clothing in terms of increasing attenuation and decreasing weight in mammography