Application of polymer composite material for radiation protection of infusion pumps

Certain cancer patients benefit from chemoradiotherapy that simultaneously applies radiation therapy and chemotherapy to targeted tissue. Infusion pumps administer the chemical agents for chemotherapy. Inadvertently during the treatment, radiation penetrating into the infusion pumps may damage the internal solid state, integrated circuit chips. Such defects may result in inaccurate dosing. Although the manuals for infusion pumps from the manufacturers warn against device use in radiological environments, the devices continue to be used during chemoradiotherapy. Proper shielding of the devices during exposure to radiation could minimize risk of device malfunction. Lead shielding has disadvantages of toxicity, weight, and bulkiness. In this study we have researched and tested potential non-lead composites for shielding. Micro particles of Bismuth (III) oxide (BO) were impregnated into two materials at various percent weights: Polydimethylsiloxane (PDMS) and Polyurethane Elastomer (PU). PDMS/BO samples attenuated X-rays of 52 kVp at 4 mm thickness. PU/BO attenuated X-rays of 52kVp at 3 mm thickness. The addition of BO to industry plastics shows promise toward use as shield to reduce risk of X-ray induced defects for infusion pumps within diagnostic ranges of radiation (1-150kVp). More development and testing are necessary to explore the effectiveness of the material at therapeutic levels (>150kVp) and to expand the potential clinical applications.