Visualization of free radical reactions in an aqueous sample irradiated by 290 MeV carbon beam.
Magn Reson Med
; 61(5): 1033-9, 2009 May.
Article
em En
| MEDLINE
| ID: mdl-19253380
ABSTRACT
The detection of free radical reactions in a gelatin sample irradiated by a heavy-ion beam was tested using electron paramagnetic resonance (EPR) spectroscopic and MRI methods. Geometry and the amount of free radical generation in a sample are described. A reaction mixture containing glutathione and a nitroxyl radical, TEMPOL, was caked with gelatin, and then irradiated with a 290 MeV carbon beam. The amount of free radical generation in a solid sample was almost flat from the surface to the beam end, except for a small peak, the peak radioactivation profile, and then steeply decreased approaching the beam end. Total free radical reactions obtained with carbon-beam irradiation were expected to be less than one-third of X-ray irradiation, when the same dose for a deeper target was considered. Both EPR and MRI are useful tools to visualize free radical generation in samples irradiated by a heavy-ion beam. The EPR-based method is more sensitive and quantitative than the MRI-based method; however, the MRI method can achieve high spatial resolution. This study gives the rationale for a redox regulation trial using antioxidant drugs to reduce the side effects on normal tissues in carbon-beam therapy.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Carbono
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Espectroscopia de Ressonância de Spin Eletrônica
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Íons Pesados
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Radicais Livres
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article