Characterization of a polymer gel dosimetry system based on N-isopropylacrylamide and N-N' methylenebisacrylamide

F. MATTEA; M. STRUMIA; M. VALENTE

MONTEVIDEO

Simposio; X LASNPA; 2014

UNIVERSIDAD DE LA REPUBLICA URUGUAY

Diagnostic radiology and radiotherapy are the most used techniques to detect and treat severalpathologies like tumor and cancer diseases. The process of radiotherapy is complex and involvesan understanding of medical physics, radiobiology, radiation safety, dosimetry, radiotherapyplanning, simulation and interaction of radiation therapy with other treatment modalities. One ofthe key aspects of radiotherapy is to determine the real dose an organ or tissue is exposed. It ispossible to measure this dose directly with the use of suitable phantoms and dosimeters. Amongthe different types of dosimeters, polymeric ones are of great interest because of their capabilityto mimic soft-tissue while maintaining a specific shape presenting high dose sensitivity and theability to retain 3D spatial dose distribution for long periods of time after being exposed. In thiswork the preparation and characterization of a polymeric dosimeter based on the monomers N-isopropylacrylamide (NIPAM), N-N?-methylenebisacrylamide (BIS) and an aqueous gelatinmatrix containing Tetrakis(hydroxymethyl)phosphonium chloride (THPC) as oxygen scavengeris studied. Different characterization techniques, such as X-ray Raman spectroscopy, confocaland scanning electronic microscopy, and absorbance/transmitance analysis of the differentdosimeters after being irradiated are presented and analyzed from a physical and chemical pointof view, in the interest of proposing new materials for specific treatment purposes.