title: Fourier transform Raman spectroscopy of polyacrylamide gels (PAGs) for radiation dosimetry.
abstract: Polyacrylamide gels (PAGs) are used for magnetic resonance imaging radiation dosimetry. Fourier transform (FT) Raman spectroscopy studies were undertaken to investigate cross-linking changes during the copolymerization of polyacrylamide gels in the spectral range of 200-3500 cm(-1). Vibrational bands of 1285 cm(-1) and 1256 cm(-1) were assigned to acrylamide and bis-acrylamide single CH2 deltaCH2 binding modes. Bands were found to decrease in amplitude with increasing absorbed radiation dose as a result of copolymerization. Principal component regression was performed on FT-Raman spectra of PAG samples irradiated to 50 Gy. Two components were found to be sufficient to account for 98.7% of the variance in the data. Cross validation was used to establish the absorbed radiation dose of an unknown PAG sample from the FT-Raman spectra. The calculated correlation coefficient between measured and predictive samples was 0.997 with a standard error of estimate of 0.976 and a standard error of prediction of 1.140. Results demonstrate the potential of FT-Raman spectroscopy for ionizing radiation dosimetry using polyacrylamide gels.
authors.affiliation: Centre for Medical and Health Physics, Queensland University of Technology, Brisbane, Australia. c.baldock@qut.edu.au
authors.forename: C
authors.initials: C
authors.lastname: Baldock
authors.forename: L
authors.initials: L
authors.lastname: Rintoul
authors.forename: S F
authors.initials: SF
authors.lastname: Keevil
authors.forename: J M
authors.initials: JM
authors.lastname: Pope
authors.forename: G A
authors.initials: GA
authors.lastname: George
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D005583:Fourier Analysis; D011874:Radiometry; D011879:Radiotherapy Dosage; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D000180:Acrylic Resins; C016680:polyacrylamide gels