Physical Sciences and Mathematics | Physics
Adam Whitten, Physics
Radiation therapy is used to treat many different types of cancer. Ionizing radiation occurs at very high frequencies and can cause reparable or permanent damage to biological cells. Cancerous tumors are typically located behind layers of healthy tissue and when radiated, the healthy and cancerous cells are damaged. With new technology, radiation machines deliver radiation such that the tissue damage is uniform as a function of tissue depth by filtering out the low-energy photons. The purpose of this research was to determine the validity of using the change in dielectric constant to gauge tissue damage due to radiation. The change in dielectric constant of beef was calculated and analyzed after each dose of two Grays of radiation, totaling four doses. One Gray of radiation is equivalent to the absorption of one joule of radiation energy by one kilogram of matter. Twelve slices of beef were stacked up with aluminum foil between each to simulate the electrodes of a capacitor so that the capacitance could be measured in between radiation doses. Differences in capacitance were converted into changes in dielectric constant. Initial analysis showed problems with the mechanics of the apparatus, particularly, slices 5, 9, 11 and 12 were deemed unusable. Using the valid slices, a weighted average change in dielectric constant per one Gray of radiation was calculated to be 0.49±0.03. Future work includes fixing problems with the apparatus, adapting this technique for living instead of dead tissue as well as determining the mathematical relationship between change in dielectric constant and cellular damage. This would also give insight to reparable damage versus permanent damage.
Jacobson, Kathryn, "Measuring Biological Cell Damage Due to Ionizing Radiation" (2015). Honors Theses, 1963-2015. 75.