Fourier transform Raman spectroscopy of polyacrylamide gels (PAGs) for radiation dosimetry.

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.

[1]  A. Nahum,et al.  The IPEMB code of practice for the determination of absorbed dose for x-rays below 300 kV generating potential (0.035 mm Al-4 mm Cu HVL; 10-300 kV generating potential). Institution of Physics and Engineering in Medicine and Biology. , 1996, Physics in medicine and biology.

[2]  R. Bansil,et al.  Raman spectroscopic and thermal studies of polyacrylamide gels with varying monomer/comonomer ratios , 1983 .

[3]  A. Boni.  A POLYACRYLAMIDE GAMMA DOSIMETER , 1961 .

[4]  T Kron,et al.  Fast T1 imaging of dual gel samples for diffusion measurements in NMR dosimetry gels. , 1997, Magnetic resonance imaging.

[5]  R. Bansil,et al.  Effect of varying crosslinking density on polyacrylamide gels , 1980 .

[6]  M. J. Day,et al.  Chemical Effects of Ionizing Radiation in some Gels , 1950, Nature.

[7]  J C Gore,et al.  Dose-response curves for Fricke-infused agarose gels as obtained by nuclear magnetic resonance. , 1990, Physics in medicine and biology.

[8]  J. L. Smith,et al.  Comparison of Vibrational Spectroscopic Techniques for the Characterization of Human Gallstones , 1995 .

[9]  L J Schreiner,et al.  Multiple-site fast exchange model for spin-lattice relaxation in the Fricke-gelatin dosimeter. , 1997, Medical physics.

[10]  A. Charlesby,et al.  The degradation of solid polymethylmethacrylate by ionizing radiation , 1954, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[11]  J C Gore,et al.  Radiation therapy dosimetry using magnetic resonance imaging of polymer gels. , 1996, Medical physics.

[12]  H. L. Andrews,et al.  Gel Dosimeter for Depth‐Dose Measurements , 1957 .

[13]  D. Massart.  Chemometrics: A Textbook , 1988 .

[14]  A. Nahum,et al.  The IPEMB code of practice for electron dosimetry for radiotherapy beams of initial energy from 2 to 50 MeV based on an air kerma calibration. Institution of Physics and Engineering in Medicine and Biology. , 1996, Physics in medicine and biology.

[15]  J. Gore,et al.  Three-dimensional visualization and measurement of conformal dose distributions using magnetic resonance imaging of BANG polymer gel dosimeters. , 1997, International journal of radiation oncology, biology, physics.

[16]  E. Wentrup-Byrne,et al.  Fourier Transform Raman Microscopic Mapping of the Molecular Components in a Human Tooth , 1997 .

[17]  B. Balcom,et al.  Diffusion in Fe(II/III) radiation dosimetry gels measured by magnetic resonance imaging. , 1995, Physics in medicine and biology.

[18]  R. Garrell,et al.  Characterization of polyacrylamide gel formation and structure by surface-enhanced Raman spectroscopy , 1988 .

[19]  J C Gore,et al.  Effects of crosslinking and temperature on the dose response of a BANG polymer gel dosimeter. , 1997, Physics in medicine and biology.

[20]  R A Schatz,et al.  Catheter-based radiotherapy to inhibit restenosis after coronary stenting. , 1997, The New England journal of medicine.

[21]  J C Gore,et al.  Magnetic resonance imaging of radiation dose distributions using a polymer-gel dosimeter , 1994, Physics in medicine and biology.

[22]  J. Gore,et al.  Measurement of radiation dose distributions by nuclear magnetic resonance (NMR) imaging. , 1984, Physics in medicine and biology.

[23]  K. Bailey,et al.  Effect of external beam irradiation on neointimal hyperplasia after experimental coronary artery injury. , 1992, Journal of the American College of Cardiology.

[24]  P. Almond,et al.  The investigation of 32P wire for catheter-based endovascular irradiation. , 1997, Medical physics.

[25]  Jan Greve,et al.  Imaging with Extrinsic Raman Labels , 1996 .

[26]  J. Gore,et al.  NMR relaxation enhancement in gels polymerized and cross-linked by ionizing radiation: a new approach to 3D dosimetry by MRI. , 1993, Magnetic resonance imaging.

[27]  A Skretting,et al.  Measurement of the ferric diffusion coefficient in agarose and gelatine gels by utilization of the evolution of a radiation induced edge as reflected in relaxation rate images. , 1997, Physics in medicine and biology.

[28]  R. Bansil,et al.  Laser Raman spectroscopy of polyacrylamide , 1981 .

[29]  S. Webb,et al.  An investigation into the dosimetry of a nine-field tomotherapy irradiation using BANG-gel dosimetry. , 1998, Physics in medicine and biology.

[30]  Bo Nordell,et al.  Diffusion of ferric ions in agarose dosimeter gels , 1992 .

[31]  C Baldock,et al.  Experimental procedure for the manufacture and calibration of polyacrylamide gel (PAG) for magnetic resonance imaging (MRI) radiation dosimetry. , 1998, Physics in medicine and biology.

[32]  C Baldock,et al.  A method for determining the diffusion coefficient in Fe(II/III) radiation dosimetry gels using finite elements. , 1996, Physics in medicine and biology.