Study and characterization of organic materials for small field dosimetry with electronic magnetic resonance

• Grant number: 13/03258-9
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): August 01, 2013
• Effective date (End): March 31, 2017
• Field of knowledge: Physical Sciences and Mathematics - Physics
• Principal Investigator: Oswaldo Baffa Filho
• Grantee: Amanda Burg Rech
• Home Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated scholarship(s): 14/02494-3 - Small field dosimetry with organic materials and Electron Magnetic Resonance spectroscopy, BE.EP.DR

Abstract

The use of small fields in radiotherapy presents some difficulties, such as dosimeters limited dimension and the absence of lateral electronic equilibrium. The high dose used makes the control and accuracy of these process being precisely assured. Among the techniques used in dosimetry there is the electron magnetic resonance (EMR) in conjunction with radiation sensitive materials. EMR spectroscopy can detect unpaired electrons which may be originated from the interaction of ionizing radiation with matter. By changing the spectrometer cavity, such as with the use of a loop-gap resonator, the sensitivity of the technique is improved, increasing the detection for small sample sizes or with small amount of material. Among the new materials used is 2-methyl-alanine and lithium formate, showing superior sensitivity than the widely recognized alanine dosimeter, efficient for low doses dosimetry (low number of spins generated by radiation) or with small dosimeter dimensions and high doses dosimetry, which have not been much explored, requiring a deeper study and characterization of these materials. To complement, computer codes are capable of simulating physical interactions in complex systems, facilitating the verification and comparison between theoretical and experimental results. Thus, this project aims the production and characterization of small 2-methyl-alanine and lithium formate dosimeters designed for small fields dosimetry in conjunction with the EMR and computer simulations obtained by Monte Carlo method.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BRAVO-MIRANDA, CARLOS; RECH, AMANDA BURG; OLIVEIRA, HARLEY FRANCISCO; BERTUCCI, EDENYSE; CORDOVA-FRAGA, TEODORO; BAFFA, OSWALDO. Measurement of rectum dose by in vivo alanine/ESR dosimetry in gynecological Ir-192 HDR brachytherapy. Radiation Measurements, v. 75, p. 45-52, APR 2015. Web of Science Citations: 2.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

RECH, Amanda Burg. Small radiation field and alternative materials in dosimetry with electron magnetic resonance spectroscopy. 2017. Doctoral Thesis - Universidade de São Paulo (USP). Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto Ribeirão Preto.